element.rs

   1use super::{
   2    display_map::{BlockContext, ToDisplayPoint},
   3    Anchor, DisplayPoint, Editor, EditorMode, EditorSnapshot, SelectPhase, SoftWrap, ToPoint,
   4    MAX_LINE_LEN,
   5};
   6use crate::{
   7    display_map::{BlockStyle, DisplaySnapshot, FoldStatus, TransformBlock},
   8    editor_settings::ShowScrollbar,
   9    git::{diff_hunk_to_display, DisplayDiffHunk},
  10    hover_popover::{
  11        hide_hover, hover_at, HOVER_POPOVER_GAP, MIN_POPOVER_CHARACTER_WIDTH,
  12        MIN_POPOVER_LINE_HEIGHT,
  13    },
  14    link_go_to_definition::{
  15        go_to_fetched_definition, go_to_fetched_type_definition, update_go_to_definition_link,
  16        update_inlay_link_and_hover_points, GoToDefinitionTrigger,
  17    },
  18    mouse_context_menu, EditorSettings, EditorStyle, GutterHover, UnfoldAt,
  19};
  20use clock::ReplicaId;
  21use collections::{BTreeMap, HashMap};
  22use git::diff::DiffHunkStatus;
  23use gpui::{
  24    color::Color,
  25    elements::*,
  26    fonts::{HighlightStyle, TextStyle, Underline},
  27    geometry::{
  28        rect::RectF,
  29        vector::{vec2f, Vector2F},
  30        PathBuilder,
  31    },
  32    json::{self, ToJson},
  33    platform::{CursorStyle, Modifiers, MouseButton, MouseButtonEvent, MouseMovedEvent},
  34    text_layout::{self, Line, RunStyle, TextLayoutCache},
  35    AnyElement, Axis, Border, CursorRegion, Element, EventContext, FontCache, LayoutContext,
  36    MouseRegion, PaintContext, Quad, SceneBuilder, SizeConstraint, ViewContext, WindowContext,
  37};
  38use itertools::Itertools;
  39use json::json;
  40use language::{
  41    language_settings::ShowWhitespaceSetting, Bias, CursorShape, DiagnosticSeverity, OffsetUtf16,
  42    Selection,
  43};
  44use project::{
  45    project_settings::{GitGutterSetting, ProjectSettings},
  46    ProjectPath,
  47};
  48use smallvec::SmallVec;
  49use std::{
  50    borrow::Cow,
  51    cmp::{self, Ordering},
  52    fmt::Write,
  53    iter,
  54    ops::Range,
  55    sync::Arc,
  56};
  57use text::Point;
  58use workspace::item::Item;
  59
  60enum FoldMarkers {}
  61
  62struct SelectionLayout {
  63    head: DisplayPoint,
  64    cursor_shape: CursorShape,
  65    is_newest: bool,
  66    is_local: bool,
  67    range: Range<DisplayPoint>,
  68    active_rows: Range<u32>,
  69}
  70
  71impl SelectionLayout {
  72    fn new<T: ToPoint + ToDisplayPoint + Clone>(
  73        selection: Selection<T>,
  74        line_mode: bool,
  75        cursor_shape: CursorShape,
  76        map: &DisplaySnapshot,
  77        is_newest: bool,
  78        is_local: bool,
  79    ) -> Self {
  80        let point_selection = selection.map(|p| p.to_point(&map.buffer_snapshot));
  81        let display_selection = point_selection.map(|p| p.to_display_point(map));
  82        let mut range = display_selection.range();
  83        let mut head = display_selection.head();
  84        let mut active_rows = map.prev_line_boundary(point_selection.start).1.row()
  85            ..map.next_line_boundary(point_selection.end).1.row();
  86
  87        // vim visual line mode
  88        if line_mode {
  89            let point_range = map.expand_to_line(point_selection.range());
  90            range = point_range.start.to_display_point(map)..point_range.end.to_display_point(map);
  91        }
  92
  93        // any vim visual mode (including line mode)
  94        if cursor_shape == CursorShape::Block && !range.is_empty() && !selection.reversed {
  95            if head.column() > 0 {
  96                head = map.clip_point(DisplayPoint::new(head.row(), head.column() - 1), Bias::Left)
  97            } else if head.row() > 0 && head != map.max_point() {
  98                head = map.clip_point(
  99                    DisplayPoint::new(head.row() - 1, map.line_len(head.row() - 1)),
 100                    Bias::Left,
 101                );
 102                // updating range.end is a no-op unless you're cursor is
 103                // on the newline containing a multi-buffer divider
 104                // in which case the clip_point may have moved the head up
 105                // an additional row.
 106                range.end = DisplayPoint::new(head.row() + 1, 0);
 107                active_rows.end = head.row();
 108            }
 109        }
 110
 111        Self {
 112            head,
 113            cursor_shape,
 114            is_newest,
 115            is_local,
 116            range,
 117            active_rows,
 118        }
 119    }
 120}
 121
 122pub struct EditorElement {
 123    style: Arc<EditorStyle>,
 124}
 125
 126impl EditorElement {
 127    pub fn new(style: EditorStyle) -> Self {
 128        Self {
 129            style: Arc::new(style),
 130        }
 131    }
 132
 133    fn attach_mouse_handlers(
 134        scene: &mut SceneBuilder,
 135        position_map: &Arc<PositionMap>,
 136        has_popovers: bool,
 137        visible_bounds: RectF,
 138        text_bounds: RectF,
 139        gutter_bounds: RectF,
 140        bounds: RectF,
 141        cx: &mut ViewContext<Editor>,
 142    ) {
 143        enum EditorElementMouseHandlers {}
 144        scene.push_mouse_region(
 145            MouseRegion::new::<EditorElementMouseHandlers>(
 146                cx.view_id(),
 147                cx.view_id(),
 148                visible_bounds,
 149            )
 150            .on_down(MouseButton::Left, {
 151                let position_map = position_map.clone();
 152                move |event, editor, cx| {
 153                    if !Self::mouse_down(
 154                        editor,
 155                        event.platform_event,
 156                        position_map.as_ref(),
 157                        text_bounds,
 158                        gutter_bounds,
 159                        cx,
 160                    ) {
 161                        cx.propagate_event();
 162                    }
 163                }
 164            })
 165            .on_down(MouseButton::Right, {
 166                let position_map = position_map.clone();
 167                move |event, editor, cx| {
 168                    if !Self::mouse_right_down(
 169                        editor,
 170                        event.position,
 171                        position_map.as_ref(),
 172                        text_bounds,
 173                        cx,
 174                    ) {
 175                        cx.propagate_event();
 176                    }
 177                }
 178            })
 179            .on_up(MouseButton::Left, {
 180                let position_map = position_map.clone();
 181                move |event, editor, cx| {
 182                    if !Self::mouse_up(
 183                        editor,
 184                        event.position,
 185                        event.cmd,
 186                        event.shift,
 187                        event.alt,
 188                        position_map.as_ref(),
 189                        text_bounds,
 190                        cx,
 191                    ) {
 192                        cx.propagate_event()
 193                    }
 194                }
 195            })
 196            .on_drag(MouseButton::Left, {
 197                let position_map = position_map.clone();
 198                move |event, editor, cx| {
 199                    if event.end {
 200                        return;
 201                    }
 202
 203                    if !Self::mouse_dragged(
 204                        editor,
 205                        event.platform_event,
 206                        position_map.as_ref(),
 207                        text_bounds,
 208                        cx,
 209                    ) {
 210                        cx.propagate_event()
 211                    }
 212                }
 213            })
 214            .on_move({
 215                let position_map = position_map.clone();
 216                move |event, editor, cx| {
 217                    if !Self::mouse_moved(
 218                        editor,
 219                        event.platform_event,
 220                        &position_map,
 221                        text_bounds,
 222                        cx,
 223                    ) {
 224                        cx.propagate_event()
 225                    }
 226                }
 227            })
 228            .on_move_out(move |_, editor: &mut Editor, cx| {
 229                if has_popovers {
 230                    hide_hover(editor, cx);
 231                }
 232            })
 233            .on_scroll({
 234                let position_map = position_map.clone();
 235                move |event, editor, cx| {
 236                    if !Self::scroll(
 237                        editor,
 238                        event.position,
 239                        *event.delta.raw(),
 240                        event.delta.precise(),
 241                        &position_map,
 242                        bounds,
 243                        cx,
 244                    ) {
 245                        cx.propagate_event()
 246                    }
 247                }
 248            }),
 249        );
 250
 251        enum GutterHandlers {}
 252        scene.push_mouse_region(
 253            MouseRegion::new::<GutterHandlers>(cx.view_id(), cx.view_id() + 1, gutter_bounds)
 254                .on_hover(|hover, editor: &mut Editor, cx| {
 255                    editor.gutter_hover(
 256                        &GutterHover {
 257                            hovered: hover.started,
 258                        },
 259                        cx,
 260                    );
 261                }),
 262        )
 263    }
 264
 265    fn mouse_down(
 266        editor: &mut Editor,
 267        MouseButtonEvent {
 268            position,
 269            modifiers:
 270                Modifiers {
 271                    shift,
 272                    ctrl,
 273                    alt,
 274                    cmd,
 275                    ..
 276                },
 277            mut click_count,
 278            ..
 279        }: MouseButtonEvent,
 280        position_map: &PositionMap,
 281        text_bounds: RectF,
 282        gutter_bounds: RectF,
 283        cx: &mut EventContext<Editor>,
 284    ) -> bool {
 285        if gutter_bounds.contains_point(position) {
 286            click_count = 3; // Simulate triple-click when clicking the gutter to select lines
 287        } else if !text_bounds.contains_point(position) {
 288            return false;
 289        }
 290
 291        let point_for_position = position_map.point_for_position(text_bounds, position);
 292        let position = point_for_position.previous_valid;
 293        if shift && alt {
 294            editor.select(
 295                SelectPhase::BeginColumnar {
 296                    position,
 297                    goal_column: point_for_position.exact_unclipped.column(),
 298                },
 299                cx,
 300            );
 301        } else if shift && !ctrl && !alt && !cmd {
 302            editor.select(
 303                SelectPhase::Extend {
 304                    position,
 305                    click_count,
 306                },
 307                cx,
 308            );
 309        } else {
 310            editor.select(
 311                SelectPhase::Begin {
 312                    position,
 313                    add: alt,
 314                    click_count,
 315                },
 316                cx,
 317            );
 318        }
 319
 320        true
 321    }
 322
 323    fn mouse_right_down(
 324        editor: &mut Editor,
 325        position: Vector2F,
 326        position_map: &PositionMap,
 327        text_bounds: RectF,
 328        cx: &mut EventContext<Editor>,
 329    ) -> bool {
 330        if !text_bounds.contains_point(position) {
 331            return false;
 332        }
 333        let point_for_position = position_map.point_for_position(text_bounds, position);
 334        mouse_context_menu::deploy_context_menu(
 335            editor,
 336            position,
 337            point_for_position.previous_valid,
 338            cx,
 339        );
 340        true
 341    }
 342
 343    fn mouse_up(
 344        editor: &mut Editor,
 345        position: Vector2F,
 346        cmd: bool,
 347        shift: bool,
 348        alt: bool,
 349        position_map: &PositionMap,
 350        text_bounds: RectF,
 351        cx: &mut EventContext<Editor>,
 352    ) -> bool {
 353        let end_selection = editor.has_pending_selection();
 354        let pending_nonempty_selections = editor.has_pending_nonempty_selection();
 355
 356        if end_selection {
 357            editor.select(SelectPhase::End, cx);
 358        }
 359
 360        if !pending_nonempty_selections && cmd && text_bounds.contains_point(position) {
 361            let point = position_map.point_for_position(text_bounds, position);
 362            let could_be_inlay = point.as_valid().is_none();
 363            if shift || could_be_inlay {
 364                go_to_fetched_type_definition(editor, point, alt, cx);
 365            } else {
 366                go_to_fetched_definition(editor, point, alt, cx);
 367            }
 368
 369            return true;
 370        }
 371
 372        end_selection
 373    }
 374
 375    fn mouse_dragged(
 376        editor: &mut Editor,
 377        MouseMovedEvent {
 378            modifiers: Modifiers { cmd, shift, .. },
 379            position,
 380            ..
 381        }: MouseMovedEvent,
 382        position_map: &PositionMap,
 383        text_bounds: RectF,
 384        cx: &mut EventContext<Editor>,
 385    ) -> bool {
 386        // This will be handled more correctly once https://github.com/zed-industries/zed/issues/1218 is completed
 387        // Don't trigger hover popover if mouse is hovering over context menu
 388        let point = if text_bounds.contains_point(position) {
 389            position_map
 390                .point_for_position(text_bounds, position)
 391                .as_valid()
 392        } else {
 393            None
 394        };
 395
 396        update_go_to_definition_link(
 397            editor,
 398            point
 399                .map(GoToDefinitionTrigger::Text)
 400                .unwrap_or(GoToDefinitionTrigger::None),
 401            cmd,
 402            shift,
 403            cx,
 404        );
 405
 406        if editor.has_pending_selection() {
 407            let mut scroll_delta = Vector2F::zero();
 408
 409            let vertical_margin = position_map.line_height.min(text_bounds.height() / 3.0);
 410            let top = text_bounds.origin_y() + vertical_margin;
 411            let bottom = text_bounds.lower_left().y() - vertical_margin;
 412            if position.y() < top {
 413                scroll_delta.set_y(-scale_vertical_mouse_autoscroll_delta(top - position.y()))
 414            }
 415            if position.y() > bottom {
 416                scroll_delta.set_y(scale_vertical_mouse_autoscroll_delta(position.y() - bottom))
 417            }
 418
 419            let horizontal_margin = position_map.line_height.min(text_bounds.width() / 3.0);
 420            let left = text_bounds.origin_x() + horizontal_margin;
 421            let right = text_bounds.upper_right().x() - horizontal_margin;
 422            if position.x() < left {
 423                scroll_delta.set_x(-scale_horizontal_mouse_autoscroll_delta(
 424                    left - position.x(),
 425                ))
 426            }
 427            if position.x() > right {
 428                scroll_delta.set_x(scale_horizontal_mouse_autoscroll_delta(
 429                    position.x() - right,
 430                ))
 431            }
 432
 433            let point_for_position = position_map.point_for_position(text_bounds, position);
 434
 435            editor.select(
 436                SelectPhase::Update {
 437                    position: point_for_position.previous_valid,
 438                    goal_column: point_for_position.exact_unclipped.column(),
 439                    scroll_position: (position_map.snapshot.scroll_position() + scroll_delta)
 440                        .clamp(Vector2F::zero(), position_map.scroll_max),
 441                },
 442                cx,
 443            );
 444            hover_at(editor, point, cx);
 445            true
 446        } else {
 447            hover_at(editor, point, cx);
 448            false
 449        }
 450    }
 451
 452    fn mouse_moved(
 453        editor: &mut Editor,
 454        MouseMovedEvent {
 455            modifiers: Modifiers { shift, cmd, .. },
 456            position,
 457            ..
 458        }: MouseMovedEvent,
 459        position_map: &PositionMap,
 460        text_bounds: RectF,
 461        cx: &mut ViewContext<Editor>,
 462    ) -> bool {
 463        // This will be handled more correctly once https://github.com/zed-industries/zed/issues/1218 is completed
 464        // Don't trigger hover popover if mouse is hovering over context menu
 465        if text_bounds.contains_point(position) {
 466            let point_for_position = position_map.point_for_position(text_bounds, position);
 467            match point_for_position.as_valid() {
 468                Some(point) => {
 469                    update_go_to_definition_link(
 470                        editor,
 471                        GoToDefinitionTrigger::Text(point),
 472                        cmd,
 473                        shift,
 474                        cx,
 475                    );
 476                    hover_at(editor, Some(point), cx);
 477                }
 478                None => {
 479                    update_inlay_link_and_hover_points(
 480                        &position_map.snapshot,
 481                        point_for_position,
 482                        editor,
 483                        cmd,
 484                        shift,
 485                        cx,
 486                    );
 487                }
 488            }
 489        } else {
 490            update_go_to_definition_link(editor, GoToDefinitionTrigger::None, cmd, shift, cx);
 491            hover_at(editor, None, cx);
 492        }
 493
 494        true
 495    }
 496
 497    fn scroll(
 498        editor: &mut Editor,
 499        position: Vector2F,
 500        mut delta: Vector2F,
 501        precise: bool,
 502        position_map: &PositionMap,
 503        bounds: RectF,
 504        cx: &mut ViewContext<Editor>,
 505    ) -> bool {
 506        if !bounds.contains_point(position) {
 507            return false;
 508        }
 509
 510        let line_height = position_map.line_height;
 511        let max_glyph_width = position_map.em_width;
 512
 513        let axis = if precise {
 514            //Trackpad
 515            position_map.snapshot.ongoing_scroll.filter(&mut delta)
 516        } else {
 517            //Not trackpad
 518            delta *= vec2f(max_glyph_width, line_height);
 519            None //Resets ongoing scroll
 520        };
 521
 522        let scroll_position = position_map.snapshot.scroll_position();
 523        let x = (scroll_position.x() * max_glyph_width - delta.x()) / max_glyph_width;
 524        let y = (scroll_position.y() * line_height - delta.y()) / line_height;
 525        let scroll_position = vec2f(x, y).clamp(Vector2F::zero(), position_map.scroll_max);
 526        editor.scroll(scroll_position, axis, cx);
 527
 528        true
 529    }
 530
 531    fn paint_background(
 532        &self,
 533        scene: &mut SceneBuilder,
 534        gutter_bounds: RectF,
 535        text_bounds: RectF,
 536        layout: &LayoutState,
 537    ) {
 538        let bounds = gutter_bounds.union_rect(text_bounds);
 539        let scroll_top =
 540            layout.position_map.snapshot.scroll_position().y() * layout.position_map.line_height;
 541        scene.push_quad(Quad {
 542            bounds: gutter_bounds,
 543            background: Some(self.style.gutter_background),
 544            border: Border::new(0., Color::transparent_black()),
 545            corner_radii: Default::default(),
 546        });
 547        scene.push_quad(Quad {
 548            bounds: text_bounds,
 549            background: Some(self.style.background),
 550            border: Border::new(0., Color::transparent_black()),
 551            corner_radii: Default::default(),
 552        });
 553
 554        if let EditorMode::Full = layout.mode {
 555            let mut active_rows = layout.active_rows.iter().peekable();
 556            while let Some((start_row, contains_non_empty_selection)) = active_rows.next() {
 557                let mut end_row = *start_row;
 558                while active_rows.peek().map_or(false, |r| {
 559                    *r.0 == end_row + 1 && r.1 == contains_non_empty_selection
 560                }) {
 561                    active_rows.next().unwrap();
 562                    end_row += 1;
 563                }
 564
 565                if !contains_non_empty_selection {
 566                    let origin = vec2f(
 567                        bounds.origin_x(),
 568                        bounds.origin_y() + (layout.position_map.line_height * *start_row as f32)
 569                            - scroll_top,
 570                    );
 571                    let size = vec2f(
 572                        bounds.width(),
 573                        layout.position_map.line_height * (end_row - start_row + 1) as f32,
 574                    );
 575                    scene.push_quad(Quad {
 576                        bounds: RectF::new(origin, size),
 577                        background: Some(self.style.active_line_background),
 578                        border: Border::default(),
 579                        corner_radii: Default::default(),
 580                    });
 581                }
 582            }
 583
 584            if let Some(highlighted_rows) = &layout.highlighted_rows {
 585                let origin = vec2f(
 586                    bounds.origin_x(),
 587                    bounds.origin_y()
 588                        + (layout.position_map.line_height * highlighted_rows.start as f32)
 589                        - scroll_top,
 590                );
 591                let size = vec2f(
 592                    bounds.width(),
 593                    layout.position_map.line_height * highlighted_rows.len() as f32,
 594                );
 595                scene.push_quad(Quad {
 596                    bounds: RectF::new(origin, size),
 597                    background: Some(self.style.highlighted_line_background),
 598                    border: Border::default(),
 599                    corner_radii: Default::default(),
 600                });
 601            }
 602
 603            let scroll_left =
 604                layout.position_map.snapshot.scroll_position().x() * layout.position_map.em_width;
 605
 606            for (wrap_position, active) in layout.wrap_guides.iter() {
 607                let x =
 608                    (text_bounds.origin_x() + wrap_position + layout.position_map.em_width / 2.)
 609                        - scroll_left;
 610
 611                if x < text_bounds.origin_x()
 612                    || (layout.show_scrollbars && x > self.scrollbar_left(&bounds))
 613                {
 614                    continue;
 615                }
 616
 617                let color = if *active {
 618                    self.style.active_wrap_guide
 619                } else {
 620                    self.style.wrap_guide
 621                };
 622                scene.push_quad(Quad {
 623                    bounds: RectF::new(
 624                        vec2f(x, text_bounds.origin_y()),
 625                        vec2f(1., text_bounds.height()),
 626                    ),
 627                    background: Some(color),
 628                    border: Border::new(0., Color::transparent_black()),
 629                    corner_radii: Default::default(),
 630                });
 631            }
 632        }
 633    }
 634
 635    fn paint_gutter(
 636        &mut self,
 637        scene: &mut SceneBuilder,
 638        bounds: RectF,
 639        visible_bounds: RectF,
 640        layout: &mut LayoutState,
 641        editor: &mut Editor,
 642        cx: &mut PaintContext<Editor>,
 643    ) {
 644        let line_height = layout.position_map.line_height;
 645
 646        let scroll_position = layout.position_map.snapshot.scroll_position();
 647        let scroll_top = scroll_position.y() * line_height;
 648
 649        let show_gutter = matches!(
 650            settings::get::<ProjectSettings>(cx).git.git_gutter,
 651            Some(GitGutterSetting::TrackedFiles)
 652        );
 653
 654        if show_gutter {
 655            Self::paint_diff_hunks(scene, bounds, layout, cx);
 656        }
 657
 658        for (ix, line) in layout.line_number_layouts.iter().enumerate() {
 659            if let Some(line) = line {
 660                let line_origin = bounds.origin()
 661                    + vec2f(
 662                        bounds.width() - line.width() - layout.gutter_padding,
 663                        ix as f32 * line_height - (scroll_top % line_height),
 664                    );
 665
 666                line.paint(scene, line_origin, visible_bounds, line_height, cx);
 667            }
 668        }
 669
 670        for (ix, fold_indicator) in layout.fold_indicators.iter_mut().enumerate() {
 671            if let Some(indicator) = fold_indicator.as_mut() {
 672                let position = vec2f(
 673                    bounds.width() - layout.gutter_padding,
 674                    ix as f32 * line_height - (scroll_top % line_height),
 675                );
 676                let centering_offset = vec2f(
 677                    (layout.gutter_padding + layout.gutter_margin - indicator.size().x()) / 2.,
 678                    (line_height - indicator.size().y()) / 2.,
 679                );
 680
 681                let indicator_origin = bounds.origin() + position + centering_offset;
 682
 683                indicator.paint(scene, indicator_origin, visible_bounds, editor, cx);
 684            }
 685        }
 686
 687        if let Some((row, indicator)) = layout.code_actions_indicator.as_mut() {
 688            let mut x = 0.;
 689            let mut y = *row as f32 * line_height - scroll_top;
 690            x += ((layout.gutter_padding + layout.gutter_margin) - indicator.size().x()) / 2.;
 691            y += (line_height - indicator.size().y()) / 2.;
 692            indicator.paint(
 693                scene,
 694                bounds.origin() + vec2f(x, y),
 695                visible_bounds,
 696                editor,
 697                cx,
 698            );
 699        }
 700    }
 701
 702    fn paint_diff_hunks(
 703        scene: &mut SceneBuilder,
 704        bounds: RectF,
 705        layout: &mut LayoutState,
 706        cx: &mut ViewContext<Editor>,
 707    ) {
 708        let diff_style = &theme::current(cx).editor.diff.clone();
 709        let line_height = layout.position_map.line_height;
 710
 711        let scroll_position = layout.position_map.snapshot.scroll_position();
 712        let scroll_top = scroll_position.y() * line_height;
 713
 714        for hunk in &layout.display_hunks {
 715            let (display_row_range, status) = match hunk {
 716                //TODO: This rendering is entirely a horrible hack
 717                &DisplayDiffHunk::Folded { display_row: row } => {
 718                    let start_y = row as f32 * line_height - scroll_top;
 719                    let end_y = start_y + line_height;
 720
 721                    let width = diff_style.removed_width_em * line_height;
 722                    let highlight_origin = bounds.origin() + vec2f(-width, start_y);
 723                    let highlight_size = vec2f(width * 2., end_y - start_y);
 724                    let highlight_bounds = RectF::new(highlight_origin, highlight_size);
 725
 726                    scene.push_quad(Quad {
 727                        bounds: highlight_bounds,
 728                        background: Some(diff_style.modified),
 729                        border: Border::new(0., Color::transparent_black()),
 730                        corner_radii: (1. * line_height).into(),
 731                    });
 732
 733                    continue;
 734                }
 735
 736                DisplayDiffHunk::Unfolded {
 737                    display_row_range,
 738                    status,
 739                } => (display_row_range, status),
 740            };
 741
 742            let color = match status {
 743                DiffHunkStatus::Added => diff_style.inserted,
 744                DiffHunkStatus::Modified => diff_style.modified,
 745
 746                //TODO: This rendering is entirely a horrible hack
 747                DiffHunkStatus::Removed => {
 748                    let row = display_row_range.start;
 749
 750                    let offset = line_height / 2.;
 751                    let start_y = row as f32 * line_height - offset - scroll_top;
 752                    let end_y = start_y + line_height;
 753
 754                    let width = diff_style.removed_width_em * line_height;
 755                    let highlight_origin = bounds.origin() + vec2f(-width, start_y);
 756                    let highlight_size = vec2f(width * 2., end_y - start_y);
 757                    let highlight_bounds = RectF::new(highlight_origin, highlight_size);
 758
 759                    scene.push_quad(Quad {
 760                        bounds: highlight_bounds,
 761                        background: Some(diff_style.deleted),
 762                        border: Border::new(0., Color::transparent_black()),
 763                        corner_radii: (1. * line_height).into(),
 764                    });
 765
 766                    continue;
 767                }
 768            };
 769
 770            let start_row = display_row_range.start;
 771            let end_row = display_row_range.end;
 772
 773            let start_y = start_row as f32 * line_height - scroll_top;
 774            let end_y = end_row as f32 * line_height - scroll_top;
 775
 776            let width = diff_style.width_em * line_height;
 777            let highlight_origin = bounds.origin() + vec2f(-width, start_y);
 778            let highlight_size = vec2f(width * 2., end_y - start_y);
 779            let highlight_bounds = RectF::new(highlight_origin, highlight_size);
 780
 781            scene.push_quad(Quad {
 782                bounds: highlight_bounds,
 783                background: Some(color),
 784                border: Border::new(0., Color::transparent_black()),
 785                corner_radii: (diff_style.corner_radius * line_height).into(),
 786            });
 787        }
 788    }
 789
 790    fn paint_text(
 791        &mut self,
 792        scene: &mut SceneBuilder,
 793        bounds: RectF,
 794        visible_bounds: RectF,
 795        layout: &mut LayoutState,
 796        editor: &mut Editor,
 797        cx: &mut PaintContext<Editor>,
 798    ) {
 799        let style = &self.style;
 800        let scroll_position = layout.position_map.snapshot.scroll_position();
 801        let start_row = layout.visible_display_row_range.start;
 802        let scroll_top = scroll_position.y() * layout.position_map.line_height;
 803        let max_glyph_width = layout.position_map.em_width;
 804        let scroll_left = scroll_position.x() * max_glyph_width;
 805        let content_origin = bounds.origin() + vec2f(layout.gutter_margin, 0.);
 806        let line_end_overshoot = 0.15 * layout.position_map.line_height;
 807        let whitespace_setting = editor.buffer.read(cx).settings_at(0, cx).show_whitespaces;
 808
 809        scene.push_layer(Some(bounds));
 810
 811        scene.push_cursor_region(CursorRegion {
 812            bounds,
 813            style: if !editor.link_go_to_definition_state.definitions.is_empty() {
 814                CursorStyle::PointingHand
 815            } else {
 816                CursorStyle::IBeam
 817            },
 818        });
 819
 820        let fold_corner_radius =
 821            self.style.folds.ellipses.corner_radius_factor * layout.position_map.line_height;
 822        for (id, range, color) in layout.fold_ranges.iter() {
 823            self.paint_highlighted_range(
 824                scene,
 825                range.clone(),
 826                *color,
 827                fold_corner_radius,
 828                fold_corner_radius * 2.,
 829                layout,
 830                content_origin,
 831                scroll_top,
 832                scroll_left,
 833                bounds,
 834            );
 835
 836            for bound in range_to_bounds(
 837                &range,
 838                content_origin,
 839                scroll_left,
 840                scroll_top,
 841                &layout.visible_display_row_range,
 842                line_end_overshoot,
 843                &layout.position_map,
 844            ) {
 845                scene.push_cursor_region(CursorRegion {
 846                    bounds: bound,
 847                    style: CursorStyle::PointingHand,
 848                });
 849
 850                let display_row = range.start.row();
 851
 852                let buffer_row = DisplayPoint::new(display_row, 0)
 853                    .to_point(&layout.position_map.snapshot.display_snapshot)
 854                    .row;
 855
 856                scene.push_mouse_region(
 857                    MouseRegion::new::<FoldMarkers>(cx.view_id(), *id as usize, bound)
 858                        .on_click(MouseButton::Left, move |_, editor: &mut Editor, cx| {
 859                            editor.unfold_at(&UnfoldAt { buffer_row }, cx)
 860                        })
 861                        .with_notify_on_hover(true)
 862                        .with_notify_on_click(true),
 863                )
 864            }
 865        }
 866
 867        for (range, color) in &layout.highlighted_ranges {
 868            self.paint_highlighted_range(
 869                scene,
 870                range.clone(),
 871                *color,
 872                0.,
 873                line_end_overshoot,
 874                layout,
 875                content_origin,
 876                scroll_top,
 877                scroll_left,
 878                bounds,
 879            );
 880        }
 881
 882        let mut cursors = SmallVec::<[Cursor; 32]>::new();
 883        let corner_radius = 0.15 * layout.position_map.line_height;
 884        let mut invisible_display_ranges = SmallVec::<[Range<DisplayPoint>; 32]>::new();
 885
 886        for (replica_id, selections) in &layout.selections {
 887            let replica_id = *replica_id;
 888            let selection_style = if let Some(replica_id) = replica_id {
 889                style.replica_selection_style(replica_id)
 890            } else {
 891                &style.absent_selection
 892            };
 893
 894            for selection in selections {
 895                self.paint_highlighted_range(
 896                    scene,
 897                    selection.range.clone(),
 898                    selection_style.selection,
 899                    corner_radius,
 900                    corner_radius * 2.,
 901                    layout,
 902                    content_origin,
 903                    scroll_top,
 904                    scroll_left,
 905                    bounds,
 906                );
 907
 908                if selection.is_local && !selection.range.is_empty() {
 909                    invisible_display_ranges.push(selection.range.clone());
 910                }
 911                if !selection.is_local || editor.show_local_cursors(cx) {
 912                    let cursor_position = selection.head;
 913                    if layout
 914                        .visible_display_row_range
 915                        .contains(&cursor_position.row())
 916                    {
 917                        let cursor_row_layout = &layout.position_map.line_layouts
 918                            [(cursor_position.row() - start_row) as usize]
 919                            .line;
 920                        let cursor_column = cursor_position.column() as usize;
 921
 922                        let cursor_character_x = cursor_row_layout.x_for_index(cursor_column);
 923                        let mut block_width =
 924                            cursor_row_layout.x_for_index(cursor_column + 1) - cursor_character_x;
 925                        if block_width == 0.0 {
 926                            block_width = layout.position_map.em_width;
 927                        }
 928                        let block_text = if let CursorShape::Block = selection.cursor_shape {
 929                            layout
 930                                .position_map
 931                                .snapshot
 932                                .chars_at(cursor_position)
 933                                .next()
 934                                .and_then(|(character, _)| {
 935                                    let font_id =
 936                                        cursor_row_layout.font_for_index(cursor_column)?;
 937                                    let text = character.to_string();
 938
 939                                    Some(cx.text_layout_cache().layout_str(
 940                                        &text,
 941                                        cursor_row_layout.font_size(),
 942                                        &[(
 943                                            text.chars().count(),
 944                                            RunStyle {
 945                                                font_id,
 946                                                color: style.background,
 947                                                underline: Default::default(),
 948                                            },
 949                                        )],
 950                                    ))
 951                                })
 952                        } else {
 953                            None
 954                        };
 955
 956                        let x = cursor_character_x - scroll_left;
 957                        let y = cursor_position.row() as f32 * layout.position_map.line_height
 958                            - scroll_top;
 959                        if selection.is_newest {
 960                            editor.pixel_position_of_newest_cursor = Some(vec2f(
 961                                bounds.origin_x() + x + block_width / 2.,
 962                                bounds.origin_y() + y + layout.position_map.line_height / 2.,
 963                            ));
 964                        }
 965                        cursors.push(Cursor {
 966                            color: selection_style.cursor,
 967                            block_width,
 968                            origin: vec2f(x, y),
 969                            line_height: layout.position_map.line_height,
 970                            shape: selection.cursor_shape,
 971                            block_text,
 972                        });
 973                    }
 974                }
 975            }
 976        }
 977
 978        if let Some(visible_text_bounds) = bounds.intersection(visible_bounds) {
 979            for (ix, line_with_invisibles) in layout.position_map.line_layouts.iter().enumerate() {
 980                let row = start_row + ix as u32;
 981                line_with_invisibles.draw(
 982                    layout,
 983                    row,
 984                    scroll_top,
 985                    scene,
 986                    content_origin,
 987                    scroll_left,
 988                    visible_text_bounds,
 989                    whitespace_setting,
 990                    &invisible_display_ranges,
 991                    visible_bounds,
 992                    cx,
 993                )
 994            }
 995        }
 996
 997        scene.paint_layer(Some(bounds), |scene| {
 998            for cursor in cursors {
 999                cursor.paint(scene, content_origin, cx);
1000            }
1001        });
1002
1003        if let Some((position, context_menu)) = layout.context_menu.as_mut() {
1004            scene.push_stacking_context(None, None);
1005            let cursor_row_layout =
1006                &layout.position_map.line_layouts[(position.row() - start_row) as usize].line;
1007            let x = cursor_row_layout.x_for_index(position.column() as usize) - scroll_left;
1008            let y = (position.row() + 1) as f32 * layout.position_map.line_height - scroll_top;
1009            let mut list_origin = content_origin + vec2f(x, y);
1010            let list_width = context_menu.size().x();
1011            let list_height = context_menu.size().y();
1012
1013            // Snap the right edge of the list to the right edge of the window if
1014            // its horizontal bounds overflow.
1015            if list_origin.x() + list_width > cx.window_size().x() {
1016                list_origin.set_x((cx.window_size().x() - list_width).max(0.));
1017            }
1018
1019            if list_origin.y() + list_height > bounds.max_y() {
1020                list_origin.set_y(list_origin.y() - layout.position_map.line_height - list_height);
1021            }
1022
1023            context_menu.paint(
1024                scene,
1025                list_origin,
1026                RectF::from_points(Vector2F::zero(), vec2f(f32::MAX, f32::MAX)), // Let content bleed outside of editor
1027                editor,
1028                cx,
1029            );
1030
1031            scene.pop_stacking_context();
1032        }
1033
1034        if let Some((position, hover_popovers)) = layout.hover_popovers.as_mut() {
1035            scene.push_stacking_context(None, None);
1036
1037            // This is safe because we check on layout whether the required row is available
1038            let hovered_row_layout =
1039                &layout.position_map.line_layouts[(position.row() - start_row) as usize].line;
1040
1041            // Minimum required size: Take the first popover, and add 1.5 times the minimum popover
1042            // height. This is the size we will use to decide whether to render popovers above or below
1043            // the hovered line.
1044            let first_size = hover_popovers[0].size();
1045            let height_to_reserve = first_size.y()
1046                + 1.5 * MIN_POPOVER_LINE_HEIGHT as f32 * layout.position_map.line_height;
1047
1048            // Compute Hovered Point
1049            let x = hovered_row_layout.x_for_index(position.column() as usize) - scroll_left;
1050            let y = position.row() as f32 * layout.position_map.line_height - scroll_top;
1051            let hovered_point = content_origin + vec2f(x, y);
1052
1053            if hovered_point.y() - height_to_reserve > 0.0 {
1054                // There is enough space above. Render popovers above the hovered point
1055                let mut current_y = hovered_point.y();
1056                for hover_popover in hover_popovers {
1057                    let size = hover_popover.size();
1058                    let mut popover_origin = vec2f(hovered_point.x(), current_y - size.y());
1059
1060                    let x_out_of_bounds = bounds.max_x() - (popover_origin.x() + size.x());
1061                    if x_out_of_bounds < 0.0 {
1062                        popover_origin.set_x(popover_origin.x() + x_out_of_bounds);
1063                    }
1064
1065                    hover_popover.paint(
1066                        scene,
1067                        popover_origin,
1068                        RectF::from_points(Vector2F::zero(), vec2f(f32::MAX, f32::MAX)), // Let content bleed outside of editor
1069                        editor,
1070                        cx,
1071                    );
1072
1073                    current_y = popover_origin.y() - HOVER_POPOVER_GAP;
1074                }
1075            } else {
1076                // There is not enough space above. Render popovers below the hovered point
1077                let mut current_y = hovered_point.y() + layout.position_map.line_height;
1078                for hover_popover in hover_popovers {
1079                    let size = hover_popover.size();
1080                    let mut popover_origin = vec2f(hovered_point.x(), current_y);
1081
1082                    let x_out_of_bounds = bounds.max_x() - (popover_origin.x() + size.x());
1083                    if x_out_of_bounds < 0.0 {
1084                        popover_origin.set_x(popover_origin.x() + x_out_of_bounds);
1085                    }
1086
1087                    hover_popover.paint(
1088                        scene,
1089                        popover_origin,
1090                        RectF::from_points(Vector2F::zero(), vec2f(f32::MAX, f32::MAX)), // Let content bleed outside of editor
1091                        editor,
1092                        cx,
1093                    );
1094
1095                    current_y = popover_origin.y() + size.y() + HOVER_POPOVER_GAP;
1096                }
1097            }
1098
1099            scene.pop_stacking_context();
1100        }
1101
1102        scene.pop_layer();
1103    }
1104
1105    fn scrollbar_left(&self, bounds: &RectF) -> f32 {
1106        bounds.max_x() - self.style.theme.scrollbar.width
1107    }
1108
1109    fn paint_scrollbar(
1110        &mut self,
1111        scene: &mut SceneBuilder,
1112        bounds: RectF,
1113        layout: &mut LayoutState,
1114        cx: &mut ViewContext<Editor>,
1115        editor: &Editor,
1116    ) {
1117        enum ScrollbarMouseHandlers {}
1118        if layout.mode != EditorMode::Full {
1119            return;
1120        }
1121
1122        let style = &self.style.theme.scrollbar;
1123
1124        let top = bounds.min_y();
1125        let bottom = bounds.max_y();
1126        let right = bounds.max_x();
1127        let left = self.scrollbar_left(&bounds);
1128        let row_range = &layout.scrollbar_row_range;
1129        let max_row = layout.max_row as f32 + (row_range.end - row_range.start);
1130
1131        let mut height = bounds.height();
1132        let mut first_row_y_offset = 0.0;
1133
1134        // Impose a minimum height on the scrollbar thumb
1135        let row_height = height / max_row;
1136        let min_thumb_height =
1137            style.min_height_factor * cx.font_cache.line_height(self.style.text.font_size);
1138        let thumb_height = (row_range.end - row_range.start) * row_height;
1139        if thumb_height < min_thumb_height {
1140            first_row_y_offset = (min_thumb_height - thumb_height) / 2.0;
1141            height -= min_thumb_height - thumb_height;
1142        }
1143
1144        let y_for_row = |row: f32| -> f32 { top + first_row_y_offset + row * row_height };
1145
1146        let thumb_top = y_for_row(row_range.start) - first_row_y_offset;
1147        let thumb_bottom = y_for_row(row_range.end) + first_row_y_offset;
1148        let track_bounds = RectF::from_points(vec2f(left, top), vec2f(right, bottom));
1149        let thumb_bounds = RectF::from_points(vec2f(left, thumb_top), vec2f(right, thumb_bottom));
1150
1151        if layout.show_scrollbars {
1152            scene.push_quad(Quad {
1153                bounds: track_bounds,
1154                border: style.track.border,
1155                background: style.track.background_color,
1156                ..Default::default()
1157            });
1158            let scrollbar_settings = settings::get::<EditorSettings>(cx).scrollbar;
1159            let theme = theme::current(cx);
1160            let scrollbar_theme = &theme.editor.scrollbar;
1161            if layout.is_singleton && scrollbar_settings.selections {
1162                let start_anchor = Anchor::min();
1163                let end_anchor = Anchor::max();
1164                let color = scrollbar_theme.selections;
1165                let border = Border {
1166                    width: 1.,
1167                    color: style.thumb.border.color,
1168                    overlay: false,
1169                    top: false,
1170                    right: true,
1171                    bottom: false,
1172                    left: true,
1173                };
1174                let mut push_region = |start: DisplayPoint, end: DisplayPoint| {
1175                    let start_y = y_for_row(start.row() as f32);
1176                    let mut end_y = y_for_row(end.row() as f32);
1177                    if end_y - start_y < 1. {
1178                        end_y = start_y + 1.;
1179                    }
1180                    let bounds = RectF::from_points(vec2f(left, start_y), vec2f(right, end_y));
1181
1182                    scene.push_quad(Quad {
1183                        bounds,
1184                        background: Some(color),
1185                        border,
1186                        corner_radii: style.thumb.corner_radii.into(),
1187                    })
1188                };
1189                let background_ranges = editor
1190                    .background_highlight_row_ranges::<crate::items::BufferSearchHighlights>(
1191                        start_anchor..end_anchor,
1192                        &layout.position_map.snapshot,
1193                        50000,
1194                    );
1195                for row in background_ranges {
1196                    let start = row.start();
1197                    let end = row.end();
1198                    push_region(*start, *end);
1199                }
1200            }
1201
1202            if layout.is_singleton && scrollbar_settings.git_diff {
1203                let diff_style = scrollbar_theme.git.clone();
1204                for hunk in layout
1205                    .position_map
1206                    .snapshot
1207                    .buffer_snapshot
1208                    .git_diff_hunks_in_range(0..(max_row.floor() as u32))
1209                {
1210                    let start_display = Point::new(hunk.buffer_range.start, 0)
1211                        .to_display_point(&layout.position_map.snapshot.display_snapshot);
1212                    let end_display = Point::new(hunk.buffer_range.end, 0)
1213                        .to_display_point(&layout.position_map.snapshot.display_snapshot);
1214                    let start_y = y_for_row(start_display.row() as f32);
1215                    let mut end_y = if hunk.buffer_range.start == hunk.buffer_range.end {
1216                        y_for_row((end_display.row() + 1) as f32)
1217                    } else {
1218                        y_for_row((end_display.row()) as f32)
1219                    };
1220
1221                    if end_y - start_y < 1. {
1222                        end_y = start_y + 1.;
1223                    }
1224                    let bounds = RectF::from_points(vec2f(left, start_y), vec2f(right, end_y));
1225
1226                    let color = match hunk.status() {
1227                        DiffHunkStatus::Added => diff_style.inserted,
1228                        DiffHunkStatus::Modified => diff_style.modified,
1229                        DiffHunkStatus::Removed => diff_style.deleted,
1230                    };
1231
1232                    let border = Border {
1233                        width: 1.,
1234                        color: style.thumb.border.color,
1235                        overlay: false,
1236                        top: false,
1237                        right: true,
1238                        bottom: false,
1239                        left: true,
1240                    };
1241
1242                    scene.push_quad(Quad {
1243                        bounds,
1244                        background: Some(color),
1245                        border,
1246                        corner_radii: style.thumb.corner_radii.into(),
1247                    })
1248                }
1249            }
1250
1251            scene.push_quad(Quad {
1252                bounds: thumb_bounds,
1253                border: style.thumb.border,
1254                background: style.thumb.background_color,
1255                corner_radii: style.thumb.corner_radii.into(),
1256            });
1257        }
1258
1259        scene.push_cursor_region(CursorRegion {
1260            bounds: track_bounds,
1261            style: CursorStyle::Arrow,
1262        });
1263        scene.push_mouse_region(
1264            MouseRegion::new::<ScrollbarMouseHandlers>(cx.view_id(), cx.view_id(), track_bounds)
1265                .on_move(move |event, editor: &mut Editor, cx| {
1266                    if event.pressed_button.is_none() {
1267                        editor.scroll_manager.show_scrollbar(cx);
1268                    }
1269                })
1270                .on_down(MouseButton::Left, {
1271                    let row_range = row_range.clone();
1272                    move |event, editor: &mut Editor, cx| {
1273                        let y = event.position.y();
1274                        if y < thumb_top || thumb_bottom < y {
1275                            let center_row = ((y - top) * max_row as f32 / height).round() as u32;
1276                            let top_row = center_row
1277                                .saturating_sub((row_range.end - row_range.start) as u32 / 2);
1278                            let mut position = editor.scroll_position(cx);
1279                            position.set_y(top_row as f32);
1280                            editor.set_scroll_position(position, cx);
1281                        } else {
1282                            editor.scroll_manager.show_scrollbar(cx);
1283                        }
1284                    }
1285                })
1286                .on_drag(MouseButton::Left, {
1287                    move |event, editor: &mut Editor, cx| {
1288                        if event.end {
1289                            return;
1290                        }
1291
1292                        let y = event.prev_mouse_position.y();
1293                        let new_y = event.position.y();
1294                        if thumb_top < y && y < thumb_bottom {
1295                            let mut position = editor.scroll_position(cx);
1296                            position.set_y(position.y() + (new_y - y) * (max_row as f32) / height);
1297                            if position.y() < 0.0 {
1298                                position.set_y(0.);
1299                            }
1300                            editor.set_scroll_position(position, cx);
1301                        }
1302                    }
1303                }),
1304        );
1305    }
1306
1307    #[allow(clippy::too_many_arguments)]
1308    fn paint_highlighted_range(
1309        &self,
1310        scene: &mut SceneBuilder,
1311        range: Range<DisplayPoint>,
1312        color: Color,
1313        corner_radius: f32,
1314        line_end_overshoot: f32,
1315        layout: &LayoutState,
1316        content_origin: Vector2F,
1317        scroll_top: f32,
1318        scroll_left: f32,
1319        bounds: RectF,
1320    ) {
1321        let start_row = layout.visible_display_row_range.start;
1322        let end_row = layout.visible_display_row_range.end;
1323        if range.start != range.end {
1324            let row_range = if range.end.column() == 0 {
1325                cmp::max(range.start.row(), start_row)..cmp::min(range.end.row(), end_row)
1326            } else {
1327                cmp::max(range.start.row(), start_row)..cmp::min(range.end.row() + 1, end_row)
1328            };
1329
1330            let highlighted_range = HighlightedRange {
1331                color,
1332                line_height: layout.position_map.line_height,
1333                corner_radius,
1334                start_y: content_origin.y()
1335                    + row_range.start as f32 * layout.position_map.line_height
1336                    - scroll_top,
1337                lines: row_range
1338                    .into_iter()
1339                    .map(|row| {
1340                        let line_layout =
1341                            &layout.position_map.line_layouts[(row - start_row) as usize].line;
1342                        HighlightedRangeLine {
1343                            start_x: if row == range.start.row() {
1344                                content_origin.x()
1345                                    + line_layout.x_for_index(range.start.column() as usize)
1346                                    - scroll_left
1347                            } else {
1348                                content_origin.x() - scroll_left
1349                            },
1350                            end_x: if row == range.end.row() {
1351                                content_origin.x()
1352                                    + line_layout.x_for_index(range.end.column() as usize)
1353                                    - scroll_left
1354                            } else {
1355                                content_origin.x() + line_layout.width() + line_end_overshoot
1356                                    - scroll_left
1357                            },
1358                        }
1359                    })
1360                    .collect(),
1361            };
1362
1363            highlighted_range.paint(bounds, scene);
1364        }
1365    }
1366
1367    fn paint_blocks(
1368        &mut self,
1369        scene: &mut SceneBuilder,
1370        bounds: RectF,
1371        visible_bounds: RectF,
1372        layout: &mut LayoutState,
1373        editor: &mut Editor,
1374        cx: &mut PaintContext<Editor>,
1375    ) {
1376        let scroll_position = layout.position_map.snapshot.scroll_position();
1377        let scroll_left = scroll_position.x() * layout.position_map.em_width;
1378        let scroll_top = scroll_position.y() * layout.position_map.line_height;
1379
1380        for block in &mut layout.blocks {
1381            let mut origin = bounds.origin()
1382                + vec2f(
1383                    0.,
1384                    block.row as f32 * layout.position_map.line_height - scroll_top,
1385                );
1386            if !matches!(block.style, BlockStyle::Sticky) {
1387                origin += vec2f(-scroll_left, 0.);
1388            }
1389            block
1390                .element
1391                .paint(scene, origin, visible_bounds, editor, cx);
1392        }
1393    }
1394
1395    fn column_pixels(&self, column: usize, cx: &ViewContext<Editor>) -> f32 {
1396        let style = &self.style;
1397
1398        cx.text_layout_cache()
1399            .layout_str(
1400                " ".repeat(column).as_str(),
1401                style.text.font_size,
1402                &[(
1403                    column,
1404                    RunStyle {
1405                        font_id: style.text.font_id,
1406                        color: Color::black(),
1407                        underline: Default::default(),
1408                    },
1409                )],
1410            )
1411            .width()
1412    }
1413
1414    fn max_line_number_width(&self, snapshot: &EditorSnapshot, cx: &ViewContext<Editor>) -> f32 {
1415        let digit_count = (snapshot.max_buffer_row() as f32 + 1.).log10().floor() as usize + 1;
1416        self.column_pixels(digit_count, cx)
1417    }
1418
1419    //Folds contained in a hunk are ignored apart from shrinking visual size
1420    //If a fold contains any hunks then that fold line is marked as modified
1421    fn layout_git_gutters(
1422        &self,
1423        display_rows: Range<u32>,
1424        snapshot: &EditorSnapshot,
1425    ) -> Vec<DisplayDiffHunk> {
1426        let buffer_snapshot = &snapshot.buffer_snapshot;
1427
1428        let buffer_start_row = DisplayPoint::new(display_rows.start, 0)
1429            .to_point(snapshot)
1430            .row;
1431        let buffer_end_row = DisplayPoint::new(display_rows.end, 0)
1432            .to_point(snapshot)
1433            .row;
1434
1435        buffer_snapshot
1436            .git_diff_hunks_in_range(buffer_start_row..buffer_end_row)
1437            .map(|hunk| diff_hunk_to_display(hunk, snapshot))
1438            .dedup()
1439            .collect()
1440    }
1441
1442    fn layout_line_numbers(
1443        &self,
1444        rows: Range<u32>,
1445        active_rows: &BTreeMap<u32, bool>,
1446        is_singleton: bool,
1447        snapshot: &EditorSnapshot,
1448        cx: &ViewContext<Editor>,
1449    ) -> (
1450        Vec<Option<text_layout::Line>>,
1451        Vec<Option<(FoldStatus, BufferRow, bool)>>,
1452    ) {
1453        let style = &self.style;
1454        let include_line_numbers = snapshot.mode == EditorMode::Full;
1455        let mut line_number_layouts = Vec::with_capacity(rows.len());
1456        let mut fold_statuses = Vec::with_capacity(rows.len());
1457        let mut line_number = String::new();
1458        for (ix, row) in snapshot
1459            .buffer_rows(rows.start)
1460            .take((rows.end - rows.start) as usize)
1461            .enumerate()
1462        {
1463            let display_row = rows.start + ix as u32;
1464            let (active, color) = if active_rows.contains_key(&display_row) {
1465                (true, style.line_number_active)
1466            } else {
1467                (false, style.line_number)
1468            };
1469            if let Some(buffer_row) = row {
1470                if include_line_numbers {
1471                    line_number.clear();
1472                    write!(&mut line_number, "{}", buffer_row + 1).unwrap();
1473                    line_number_layouts.push(Some(cx.text_layout_cache().layout_str(
1474                        &line_number,
1475                        style.text.font_size,
1476                        &[(
1477                            line_number.len(),
1478                            RunStyle {
1479                                font_id: style.text.font_id,
1480                                color,
1481                                underline: Default::default(),
1482                            },
1483                        )],
1484                    )));
1485                    fold_statuses.push(
1486                        is_singleton
1487                            .then(|| {
1488                                snapshot
1489                                    .fold_for_line(buffer_row)
1490                                    .map(|fold_status| (fold_status, buffer_row, active))
1491                            })
1492                            .flatten(),
1493                    )
1494                }
1495            } else {
1496                fold_statuses.push(None);
1497                line_number_layouts.push(None);
1498            }
1499        }
1500
1501        (line_number_layouts, fold_statuses)
1502    }
1503
1504    fn layout_lines(
1505        &mut self,
1506        rows: Range<u32>,
1507        line_number_layouts: &[Option<Line>],
1508        snapshot: &EditorSnapshot,
1509        cx: &ViewContext<Editor>,
1510    ) -> Vec<LineWithInvisibles> {
1511        if rows.start >= rows.end {
1512            return Vec::new();
1513        }
1514
1515        // When the editor is empty and unfocused, then show the placeholder.
1516        if snapshot.is_empty() {
1517            let placeholder_style = self
1518                .style
1519                .placeholder_text
1520                .as_ref()
1521                .unwrap_or(&self.style.text);
1522            let placeholder_text = snapshot.placeholder_text();
1523            let placeholder_lines = placeholder_text
1524                .as_ref()
1525                .map_or("", AsRef::as_ref)
1526                .split('\n')
1527                .skip(rows.start as usize)
1528                .chain(iter::repeat(""))
1529                .take(rows.len());
1530            placeholder_lines
1531                .map(|line| {
1532                    cx.text_layout_cache().layout_str(
1533                        line,
1534                        placeholder_style.font_size,
1535                        &[(
1536                            line.len(),
1537                            RunStyle {
1538                                font_id: placeholder_style.font_id,
1539                                color: placeholder_style.color,
1540                                underline: Default::default(),
1541                            },
1542                        )],
1543                    )
1544                })
1545                .map(|line| LineWithInvisibles {
1546                    line,
1547                    invisibles: Vec::new(),
1548                })
1549                .collect()
1550        } else {
1551            let style = &self.style;
1552            let chunks = snapshot
1553                .chunks(
1554                    rows.clone(),
1555                    true,
1556                    Some(style.theme.hint),
1557                    Some(style.theme.suggestion),
1558                )
1559                .map(|chunk| {
1560                    let mut highlight_style = chunk
1561                        .syntax_highlight_id
1562                        .and_then(|id| id.style(&style.syntax));
1563
1564                    if let Some(chunk_highlight) = chunk.highlight_style {
1565                        if let Some(highlight_style) = highlight_style.as_mut() {
1566                            highlight_style.highlight(chunk_highlight);
1567                        } else {
1568                            highlight_style = Some(chunk_highlight);
1569                        }
1570                    }
1571
1572                    let mut diagnostic_highlight = HighlightStyle::default();
1573
1574                    if chunk.is_unnecessary {
1575                        diagnostic_highlight.fade_out = Some(style.unnecessary_code_fade);
1576                    }
1577
1578                    if let Some(severity) = chunk.diagnostic_severity {
1579                        // Omit underlines for HINT/INFO diagnostics on 'unnecessary' code.
1580                        if severity <= DiagnosticSeverity::WARNING || !chunk.is_unnecessary {
1581                            let diagnostic_style = super::diagnostic_style(severity, true, style);
1582                            diagnostic_highlight.underline = Some(Underline {
1583                                color: Some(diagnostic_style.message.text.color),
1584                                thickness: 1.0.into(),
1585                                squiggly: true,
1586                            });
1587                        }
1588                    }
1589
1590                    if let Some(highlight_style) = highlight_style.as_mut() {
1591                        highlight_style.highlight(diagnostic_highlight);
1592                    } else {
1593                        highlight_style = Some(diagnostic_highlight);
1594                    }
1595
1596                    HighlightedChunk {
1597                        chunk: chunk.text,
1598                        style: highlight_style,
1599                        is_tab: chunk.is_tab,
1600                    }
1601                });
1602
1603            LineWithInvisibles::from_chunks(
1604                chunks,
1605                &style.text,
1606                cx.text_layout_cache(),
1607                cx.font_cache(),
1608                MAX_LINE_LEN,
1609                rows.len() as usize,
1610                line_number_layouts,
1611                snapshot.mode,
1612            )
1613        }
1614    }
1615
1616    #[allow(clippy::too_many_arguments)]
1617    fn layout_blocks(
1618        &mut self,
1619        rows: Range<u32>,
1620        snapshot: &EditorSnapshot,
1621        editor_width: f32,
1622        scroll_width: f32,
1623        gutter_padding: f32,
1624        gutter_width: f32,
1625        em_width: f32,
1626        text_x: f32,
1627        line_height: f32,
1628        style: &EditorStyle,
1629        line_layouts: &[LineWithInvisibles],
1630        editor: &mut Editor,
1631        cx: &mut LayoutContext<Editor>,
1632    ) -> (f32, Vec<BlockLayout>) {
1633        let mut block_id = 0;
1634        let scroll_x = snapshot.scroll_anchor.offset.x();
1635        let (fixed_blocks, non_fixed_blocks) = snapshot
1636            .blocks_in_range(rows.clone())
1637            .partition::<Vec<_>, _>(|(_, block)| match block {
1638                TransformBlock::ExcerptHeader { .. } => false,
1639                TransformBlock::Custom(block) => block.style() == BlockStyle::Fixed,
1640            });
1641        let mut render_block = |block: &TransformBlock, width: f32, block_id: usize| {
1642            let mut element = match block {
1643                TransformBlock::Custom(block) => {
1644                    let align_to = block
1645                        .position()
1646                        .to_point(&snapshot.buffer_snapshot)
1647                        .to_display_point(snapshot);
1648                    let anchor_x = text_x
1649                        + if rows.contains(&align_to.row()) {
1650                            line_layouts[(align_to.row() - rows.start) as usize]
1651                                .line
1652                                .x_for_index(align_to.column() as usize)
1653                        } else {
1654                            layout_line(align_to.row(), snapshot, style, cx.text_layout_cache())
1655                                .x_for_index(align_to.column() as usize)
1656                        };
1657
1658                    block.render(&mut BlockContext {
1659                        view_context: cx,
1660                        anchor_x,
1661                        gutter_padding,
1662                        line_height,
1663                        scroll_x,
1664                        gutter_width,
1665                        em_width,
1666                        block_id,
1667                    })
1668                }
1669                TransformBlock::ExcerptHeader {
1670                    id,
1671                    buffer,
1672                    range,
1673                    starts_new_buffer,
1674                    ..
1675                } => {
1676                    let tooltip_style = theme::current(cx).tooltip.clone();
1677                    let include_root = editor
1678                        .project
1679                        .as_ref()
1680                        .map(|project| project.read(cx).visible_worktrees(cx).count() > 1)
1681                        .unwrap_or_default();
1682                    let jump_icon = project::File::from_dyn(buffer.file()).map(|file| {
1683                        let jump_path = ProjectPath {
1684                            worktree_id: file.worktree_id(cx),
1685                            path: file.path.clone(),
1686                        };
1687                        let jump_anchor = range
1688                            .primary
1689                            .as_ref()
1690                            .map_or(range.context.start, |primary| primary.start);
1691                        let jump_position = language::ToPoint::to_point(&jump_anchor, buffer);
1692
1693                        enum JumpIcon {}
1694                        MouseEventHandler::new::<JumpIcon, _>((*id).into(), cx, |state, _| {
1695                            let style = style.jump_icon.style_for(state);
1696                            Svg::new("icons/arrow_up_right_8.svg")
1697                                .with_color(style.color)
1698                                .constrained()
1699                                .with_width(style.icon_width)
1700                                .aligned()
1701                                .contained()
1702                                .with_style(style.container)
1703                                .constrained()
1704                                .with_width(style.button_width)
1705                                .with_height(style.button_width)
1706                        })
1707                        .with_cursor_style(CursorStyle::PointingHand)
1708                        .on_click(MouseButton::Left, move |_, editor, cx| {
1709                            if let Some(workspace) = editor
1710                                .workspace
1711                                .as_ref()
1712                                .and_then(|(workspace, _)| workspace.upgrade(cx))
1713                            {
1714                                workspace.update(cx, |workspace, cx| {
1715                                    Editor::jump(
1716                                        workspace,
1717                                        jump_path.clone(),
1718                                        jump_position,
1719                                        jump_anchor,
1720                                        cx,
1721                                    );
1722                                });
1723                            }
1724                        })
1725                        .with_tooltip::<JumpIcon>(
1726                            (*id).into(),
1727                            "Jump to Buffer".to_string(),
1728                            Some(Box::new(crate::OpenExcerpts)),
1729                            tooltip_style.clone(),
1730                            cx,
1731                        )
1732                        .aligned()
1733                        .flex_float()
1734                    });
1735
1736                    if *starts_new_buffer {
1737                        let editor_font_size = style.text.font_size;
1738                        let style = &style.diagnostic_path_header;
1739                        let font_size = (style.text_scale_factor * editor_font_size).round();
1740
1741                        let path = buffer.resolve_file_path(cx, include_root);
1742                        let mut filename = None;
1743                        let mut parent_path = None;
1744                        // Can't use .and_then() because `.file_name()` and `.parent()` return references :(
1745                        if let Some(path) = path {
1746                            filename = path.file_name().map(|f| f.to_string_lossy().to_string());
1747                            parent_path =
1748                                path.parent().map(|p| p.to_string_lossy().to_string() + "/");
1749                        }
1750
1751                        Flex::row()
1752                            .with_child(
1753                                Label::new(
1754                                    filename.unwrap_or_else(|| "untitled".to_string()),
1755                                    style.filename.text.clone().with_font_size(font_size),
1756                                )
1757                                .contained()
1758                                .with_style(style.filename.container)
1759                                .aligned(),
1760                            )
1761                            .with_children(parent_path.map(|path| {
1762                                Label::new(path, style.path.text.clone().with_font_size(font_size))
1763                                    .contained()
1764                                    .with_style(style.path.container)
1765                                    .aligned()
1766                            }))
1767                            .with_children(jump_icon)
1768                            .contained()
1769                            .with_style(style.container)
1770                            .with_padding_left(gutter_padding)
1771                            .with_padding_right(gutter_padding)
1772                            .expanded()
1773                            .into_any_named("path header block")
1774                    } else {
1775                        let text_style = style.text.clone();
1776                        Flex::row()
1777                            .with_child(Label::new("", text_style))
1778                            .with_children(jump_icon)
1779                            .contained()
1780                            .with_padding_left(gutter_padding)
1781                            .with_padding_right(gutter_padding)
1782                            .expanded()
1783                            .into_any_named("collapsed context")
1784                    }
1785                }
1786            };
1787
1788            element.layout(
1789                SizeConstraint {
1790                    min: Vector2F::zero(),
1791                    max: vec2f(width, block.height() as f32 * line_height),
1792                },
1793                editor,
1794                cx,
1795            );
1796            element
1797        };
1798
1799        let mut fixed_block_max_width = 0f32;
1800        let mut blocks = Vec::new();
1801        for (row, block) in fixed_blocks {
1802            let element = render_block(block, f32::INFINITY, block_id);
1803            block_id += 1;
1804            fixed_block_max_width = fixed_block_max_width.max(element.size().x() + em_width);
1805            blocks.push(BlockLayout {
1806                row,
1807                element,
1808                style: BlockStyle::Fixed,
1809            });
1810        }
1811        for (row, block) in non_fixed_blocks {
1812            let style = match block {
1813                TransformBlock::Custom(block) => block.style(),
1814                TransformBlock::ExcerptHeader { .. } => BlockStyle::Sticky,
1815            };
1816            let width = match style {
1817                BlockStyle::Sticky => editor_width,
1818                BlockStyle::Flex => editor_width
1819                    .max(fixed_block_max_width)
1820                    .max(gutter_width + scroll_width),
1821                BlockStyle::Fixed => unreachable!(),
1822            };
1823            let element = render_block(block, width, block_id);
1824            block_id += 1;
1825            blocks.push(BlockLayout {
1826                row,
1827                element,
1828                style,
1829            });
1830        }
1831        (
1832            scroll_width.max(fixed_block_max_width - gutter_width),
1833            blocks,
1834        )
1835    }
1836}
1837
1838struct HighlightedChunk<'a> {
1839    chunk: &'a str,
1840    style: Option<HighlightStyle>,
1841    is_tab: bool,
1842}
1843
1844#[derive(Debug)]
1845pub struct LineWithInvisibles {
1846    pub line: Line,
1847    invisibles: Vec<Invisible>,
1848}
1849
1850impl LineWithInvisibles {
1851    fn from_chunks<'a>(
1852        chunks: impl Iterator<Item = HighlightedChunk<'a>>,
1853        text_style: &TextStyle,
1854        text_layout_cache: &TextLayoutCache,
1855        font_cache: &Arc<FontCache>,
1856        max_line_len: usize,
1857        max_line_count: usize,
1858        line_number_layouts: &[Option<Line>],
1859        editor_mode: EditorMode,
1860    ) -> Vec<Self> {
1861        let mut layouts = Vec::with_capacity(max_line_count);
1862        let mut line = String::new();
1863        let mut invisibles = Vec::new();
1864        let mut styles = Vec::new();
1865        let mut non_whitespace_added = false;
1866        let mut row = 0;
1867        let mut line_exceeded_max_len = false;
1868        for highlighted_chunk in chunks.chain([HighlightedChunk {
1869            chunk: "\n",
1870            style: None,
1871            is_tab: false,
1872        }]) {
1873            for (ix, mut line_chunk) in highlighted_chunk.chunk.split('\n').enumerate() {
1874                if ix > 0 {
1875                    layouts.push(Self {
1876                        line: text_layout_cache.layout_str(&line, text_style.font_size, &styles),
1877                        invisibles: invisibles.drain(..).collect(),
1878                    });
1879
1880                    line.clear();
1881                    styles.clear();
1882                    row += 1;
1883                    line_exceeded_max_len = false;
1884                    non_whitespace_added = false;
1885                    if row == max_line_count {
1886                        return layouts;
1887                    }
1888                }
1889
1890                if !line_chunk.is_empty() && !line_exceeded_max_len {
1891                    let text_style = if let Some(style) = highlighted_chunk.style {
1892                        text_style
1893                            .clone()
1894                            .highlight(style, font_cache)
1895                            .map(Cow::Owned)
1896                            .unwrap_or_else(|_| Cow::Borrowed(text_style))
1897                    } else {
1898                        Cow::Borrowed(text_style)
1899                    };
1900
1901                    if line.len() + line_chunk.len() > max_line_len {
1902                        let mut chunk_len = max_line_len - line.len();
1903                        while !line_chunk.is_char_boundary(chunk_len) {
1904                            chunk_len -= 1;
1905                        }
1906                        line_chunk = &line_chunk[..chunk_len];
1907                        line_exceeded_max_len = true;
1908                    }
1909
1910                    styles.push((
1911                        line_chunk.len(),
1912                        RunStyle {
1913                            font_id: text_style.font_id,
1914                            color: text_style.color,
1915                            underline: text_style.underline,
1916                        },
1917                    ));
1918
1919                    if editor_mode == EditorMode::Full {
1920                        // Line wrap pads its contents with fake whitespaces,
1921                        // avoid printing them
1922                        let inside_wrapped_string = line_number_layouts
1923                            .get(row)
1924                            .and_then(|layout| layout.as_ref())
1925                            .is_none();
1926                        if highlighted_chunk.is_tab {
1927                            if non_whitespace_added || !inside_wrapped_string {
1928                                invisibles.push(Invisible::Tab {
1929                                    line_start_offset: line.len(),
1930                                });
1931                            }
1932                        } else {
1933                            invisibles.extend(
1934                                line_chunk
1935                                    .chars()
1936                                    .enumerate()
1937                                    .filter(|(_, line_char)| {
1938                                        let is_whitespace = line_char.is_whitespace();
1939                                        non_whitespace_added |= !is_whitespace;
1940                                        is_whitespace
1941                                            && (non_whitespace_added || !inside_wrapped_string)
1942                                    })
1943                                    .map(|(whitespace_index, _)| Invisible::Whitespace {
1944                                        line_offset: line.len() + whitespace_index,
1945                                    }),
1946                            )
1947                        }
1948                    }
1949
1950                    line.push_str(line_chunk);
1951                }
1952            }
1953        }
1954
1955        layouts
1956    }
1957
1958    fn draw(
1959        &self,
1960        layout: &LayoutState,
1961        row: u32,
1962        scroll_top: f32,
1963        scene: &mut SceneBuilder,
1964        content_origin: Vector2F,
1965        scroll_left: f32,
1966        visible_text_bounds: RectF,
1967        whitespace_setting: ShowWhitespaceSetting,
1968        selection_ranges: &[Range<DisplayPoint>],
1969        visible_bounds: RectF,
1970        cx: &mut ViewContext<Editor>,
1971    ) {
1972        let line_height = layout.position_map.line_height;
1973        let line_y = row as f32 * line_height - scroll_top;
1974
1975        self.line.paint(
1976            scene,
1977            content_origin + vec2f(-scroll_left, line_y),
1978            visible_text_bounds,
1979            line_height,
1980            cx,
1981        );
1982
1983        self.draw_invisibles(
1984            &selection_ranges,
1985            layout,
1986            content_origin,
1987            scroll_left,
1988            line_y,
1989            row,
1990            scene,
1991            visible_bounds,
1992            line_height,
1993            whitespace_setting,
1994            cx,
1995        );
1996    }
1997
1998    fn draw_invisibles(
1999        &self,
2000        selection_ranges: &[Range<DisplayPoint>],
2001        layout: &LayoutState,
2002        content_origin: Vector2F,
2003        scroll_left: f32,
2004        line_y: f32,
2005        row: u32,
2006        scene: &mut SceneBuilder,
2007        visible_bounds: RectF,
2008        line_height: f32,
2009        whitespace_setting: ShowWhitespaceSetting,
2010        cx: &mut ViewContext<Editor>,
2011    ) {
2012        let allowed_invisibles_regions = match whitespace_setting {
2013            ShowWhitespaceSetting::None => return,
2014            ShowWhitespaceSetting::Selection => Some(selection_ranges),
2015            ShowWhitespaceSetting::All => None,
2016        };
2017
2018        for invisible in &self.invisibles {
2019            let (&token_offset, invisible_symbol) = match invisible {
2020                Invisible::Tab { line_start_offset } => (line_start_offset, &layout.tab_invisible),
2021                Invisible::Whitespace { line_offset } => (line_offset, &layout.space_invisible),
2022            };
2023
2024            let x_offset = self.line.x_for_index(token_offset);
2025            let invisible_offset =
2026                (layout.position_map.em_width - invisible_symbol.width()).max(0.0) / 2.0;
2027            let origin = content_origin + vec2f(-scroll_left + x_offset + invisible_offset, line_y);
2028
2029            if let Some(allowed_regions) = allowed_invisibles_regions {
2030                let invisible_point = DisplayPoint::new(row, token_offset as u32);
2031                if !allowed_regions
2032                    .iter()
2033                    .any(|region| region.start <= invisible_point && invisible_point < region.end)
2034                {
2035                    continue;
2036                }
2037            }
2038            invisible_symbol.paint(scene, origin, visible_bounds, line_height, cx);
2039        }
2040    }
2041}
2042
2043#[derive(Debug, Clone, Copy, PartialEq, Eq)]
2044enum Invisible {
2045    Tab { line_start_offset: usize },
2046    Whitespace { line_offset: usize },
2047}
2048
2049impl Element<Editor> for EditorElement {
2050    type LayoutState = LayoutState;
2051    type PaintState = ();
2052
2053    fn layout(
2054        &mut self,
2055        constraint: SizeConstraint,
2056        editor: &mut Editor,
2057        cx: &mut LayoutContext<Editor>,
2058    ) -> (Vector2F, Self::LayoutState) {
2059        let mut size = constraint.max;
2060        if size.x().is_infinite() {
2061            unimplemented!("we don't yet handle an infinite width constraint on buffer elements");
2062        }
2063
2064        let snapshot = editor.snapshot(cx);
2065        let style = self.style.clone();
2066
2067        let line_height = (style.text.font_size * style.line_height_scalar).round();
2068
2069        let gutter_padding;
2070        let gutter_width;
2071        let gutter_margin;
2072        if snapshot.show_gutter {
2073            let em_width = style.text.em_width(cx.font_cache());
2074            gutter_padding = (em_width * style.gutter_padding_factor).round();
2075            gutter_width = self.max_line_number_width(&snapshot, cx) + gutter_padding * 2.0;
2076            gutter_margin = -style.text.descent(cx.font_cache());
2077        } else {
2078            gutter_padding = 0.0;
2079            gutter_width = 0.0;
2080            gutter_margin = 0.0;
2081        };
2082
2083        let text_width = size.x() - gutter_width;
2084        let em_width = style.text.em_width(cx.font_cache());
2085        let em_advance = style.text.em_advance(cx.font_cache());
2086        let overscroll = vec2f(em_width, 0.);
2087        let snapshot = {
2088            editor.set_visible_line_count(size.y() / line_height, cx);
2089
2090            let editor_width = text_width - gutter_margin - overscroll.x() - em_width;
2091            let wrap_width = match editor.soft_wrap_mode(cx) {
2092                SoftWrap::None => (MAX_LINE_LEN / 2) as f32 * em_advance,
2093                SoftWrap::EditorWidth => editor_width,
2094                SoftWrap::Column(column) => editor_width.min(column as f32 * em_advance),
2095            };
2096
2097            if editor.set_wrap_width(Some(wrap_width), cx) {
2098                editor.snapshot(cx)
2099            } else {
2100                snapshot
2101            }
2102        };
2103
2104        let wrap_guides = editor
2105            .wrap_guides(cx)
2106            .iter()
2107            .map(|(guide, active)| (self.column_pixels(*guide, cx), *active))
2108            .collect();
2109
2110        let scroll_height = (snapshot.max_point().row() + 1) as f32 * line_height;
2111        if let EditorMode::AutoHeight { max_lines } = snapshot.mode {
2112            size.set_y(
2113                scroll_height
2114                    .min(constraint.max_along(Axis::Vertical))
2115                    .max(constraint.min_along(Axis::Vertical))
2116                    .max(line_height)
2117                    .min(line_height * max_lines as f32),
2118            )
2119        } else if let EditorMode::SingleLine = snapshot.mode {
2120            size.set_y(line_height.max(constraint.min_along(Axis::Vertical)))
2121        } else if size.y().is_infinite() {
2122            size.set_y(scroll_height);
2123        }
2124        let gutter_size = vec2f(gutter_width, size.y());
2125        let text_size = vec2f(text_width, size.y());
2126
2127        let autoscroll_horizontally = editor.autoscroll_vertically(size.y(), line_height, cx);
2128        let mut snapshot = editor.snapshot(cx);
2129
2130        let scroll_position = snapshot.scroll_position();
2131        // The scroll position is a fractional point, the whole number of which represents
2132        // the top of the window in terms of display rows.
2133        let start_row = scroll_position.y() as u32;
2134        let height_in_lines = size.y() / line_height;
2135        let max_row = snapshot.max_point().row();
2136
2137        // Add 1 to ensure selections bleed off screen
2138        let end_row = 1 + cmp::min(
2139            (scroll_position.y() + height_in_lines).ceil() as u32,
2140            max_row,
2141        );
2142
2143        let start_anchor = if start_row == 0 {
2144            Anchor::min()
2145        } else {
2146            snapshot
2147                .buffer_snapshot
2148                .anchor_before(DisplayPoint::new(start_row, 0).to_offset(&snapshot, Bias::Left))
2149        };
2150        let end_anchor = if end_row > max_row {
2151            Anchor::max()
2152        } else {
2153            snapshot
2154                .buffer_snapshot
2155                .anchor_before(DisplayPoint::new(end_row, 0).to_offset(&snapshot, Bias::Right))
2156        };
2157
2158        let mut selections: Vec<(Option<ReplicaId>, Vec<SelectionLayout>)> = Vec::new();
2159        let mut active_rows = BTreeMap::new();
2160        let mut fold_ranges = Vec::new();
2161        let is_singleton = editor.is_singleton(cx);
2162
2163        let highlighted_rows = editor.highlighted_rows();
2164        let theme = theme::current(cx);
2165        let highlighted_ranges = editor.background_highlights_in_range(
2166            start_anchor..end_anchor,
2167            &snapshot.display_snapshot,
2168            theme.as_ref(),
2169        );
2170
2171        fold_ranges.extend(
2172            snapshot
2173                .folds_in_range(start_anchor..end_anchor)
2174                .map(|anchor| {
2175                    let start = anchor.start.to_point(&snapshot.buffer_snapshot);
2176                    (
2177                        start.row,
2178                        start.to_display_point(&snapshot.display_snapshot)
2179                            ..anchor.end.to_display_point(&snapshot),
2180                    )
2181                }),
2182        );
2183
2184        let mut remote_selections = HashMap::default();
2185        for (replica_id, line_mode, cursor_shape, selection) in snapshot
2186            .buffer_snapshot
2187            .remote_selections_in_range(&(start_anchor..end_anchor))
2188        {
2189            let replica_id = if let Some(mapping) = &editor.replica_id_mapping {
2190                mapping.get(&replica_id).copied()
2191            } else {
2192                None
2193            };
2194
2195            // The local selections match the leader's selections.
2196            if replica_id.is_some() && replica_id == editor.leader_replica_id {
2197                continue;
2198            }
2199            remote_selections
2200                .entry(replica_id)
2201                .or_insert(Vec::new())
2202                .push(SelectionLayout::new(
2203                    selection,
2204                    line_mode,
2205                    cursor_shape,
2206                    &snapshot.display_snapshot,
2207                    false,
2208                    false,
2209                ));
2210        }
2211        selections.extend(remote_selections);
2212
2213        let mut newest_selection_head = None;
2214
2215        if editor.show_local_selections {
2216            let mut local_selections: Vec<Selection<Point>> = editor
2217                .selections
2218                .disjoint_in_range(start_anchor..end_anchor, cx);
2219            local_selections.extend(editor.selections.pending(cx));
2220            let mut layouts = Vec::new();
2221            let newest = editor.selections.newest(cx);
2222            for selection in local_selections.drain(..) {
2223                let is_empty = selection.start == selection.end;
2224                let is_newest = selection == newest;
2225
2226                let layout = SelectionLayout::new(
2227                    selection,
2228                    editor.selections.line_mode,
2229                    editor.cursor_shape,
2230                    &snapshot.display_snapshot,
2231                    is_newest,
2232                    true,
2233                );
2234                if is_newest {
2235                    newest_selection_head = Some(layout.head);
2236                }
2237
2238                for row in cmp::max(layout.active_rows.start, start_row)
2239                    ..=cmp::min(layout.active_rows.end, end_row)
2240                {
2241                    let contains_non_empty_selection = active_rows.entry(row).or_insert(!is_empty);
2242                    *contains_non_empty_selection |= !is_empty;
2243                }
2244                layouts.push(layout);
2245            }
2246
2247            // Render the local selections in the leader's color when following.
2248            let local_replica_id = if let Some(leader_replica_id) = editor.leader_replica_id {
2249                leader_replica_id
2250            } else {
2251                let replica_id = editor.replica_id(cx);
2252                if let Some(mapping) = &editor.replica_id_mapping {
2253                    mapping.get(&replica_id).copied().unwrap_or(replica_id)
2254                } else {
2255                    replica_id
2256                }
2257            };
2258
2259            selections.push((Some(local_replica_id), layouts));
2260        }
2261
2262        let scrollbar_settings = &settings::get::<EditorSettings>(cx).scrollbar;
2263        let show_scrollbars = match scrollbar_settings.show {
2264            ShowScrollbar::Auto => {
2265                // Git
2266                (is_singleton && scrollbar_settings.git_diff && snapshot.buffer_snapshot.has_git_diffs())
2267                ||
2268                // Selections
2269                (is_singleton && scrollbar_settings.selections && !highlighted_ranges.is_empty())
2270                // Scrollmanager
2271                || editor.scroll_manager.scrollbars_visible()
2272            }
2273            ShowScrollbar::System => editor.scroll_manager.scrollbars_visible(),
2274            ShowScrollbar::Always => true,
2275            ShowScrollbar::Never => false,
2276        };
2277
2278        let fold_ranges: Vec<(BufferRow, Range<DisplayPoint>, Color)> = fold_ranges
2279            .into_iter()
2280            .map(|(id, fold)| {
2281                let color = self
2282                    .style
2283                    .folds
2284                    .ellipses
2285                    .background
2286                    .style_for(&mut cx.mouse_state::<FoldMarkers>(id as usize))
2287                    .color;
2288
2289                (id, fold, color)
2290            })
2291            .collect();
2292
2293        let (line_number_layouts, fold_statuses) = self.layout_line_numbers(
2294            start_row..end_row,
2295            &active_rows,
2296            is_singleton,
2297            &snapshot,
2298            cx,
2299        );
2300
2301        let display_hunks = self.layout_git_gutters(start_row..end_row, &snapshot);
2302
2303        let scrollbar_row_range = scroll_position.y()..(scroll_position.y() + height_in_lines);
2304
2305        let mut max_visible_line_width = 0.0;
2306        let line_layouts =
2307            self.layout_lines(start_row..end_row, &line_number_layouts, &snapshot, cx);
2308        for line_with_invisibles in &line_layouts {
2309            if line_with_invisibles.line.width() > max_visible_line_width {
2310                max_visible_line_width = line_with_invisibles.line.width();
2311            }
2312        }
2313
2314        let style = self.style.clone();
2315        let longest_line_width = layout_line(
2316            snapshot.longest_row(),
2317            &snapshot,
2318            &style,
2319            cx.text_layout_cache(),
2320        )
2321        .width();
2322        let scroll_width = longest_line_width.max(max_visible_line_width) + overscroll.x();
2323        let em_width = style.text.em_width(cx.font_cache());
2324        let (scroll_width, blocks) = self.layout_blocks(
2325            start_row..end_row,
2326            &snapshot,
2327            size.x(),
2328            scroll_width,
2329            gutter_padding,
2330            gutter_width,
2331            em_width,
2332            gutter_width + gutter_margin,
2333            line_height,
2334            &style,
2335            &line_layouts,
2336            editor,
2337            cx,
2338        );
2339
2340        let scroll_max = vec2f(
2341            ((scroll_width - text_size.x()) / em_width).max(0.0),
2342            max_row as f32,
2343        );
2344
2345        let clamped = editor.scroll_manager.clamp_scroll_left(scroll_max.x());
2346
2347        let autoscrolled = if autoscroll_horizontally {
2348            editor.autoscroll_horizontally(
2349                start_row,
2350                text_size.x(),
2351                scroll_width,
2352                em_width,
2353                &line_layouts,
2354                cx,
2355            )
2356        } else {
2357            false
2358        };
2359
2360        if clamped || autoscrolled {
2361            snapshot = editor.snapshot(cx);
2362        }
2363
2364        let style = editor.style(cx);
2365
2366        let mut context_menu = None;
2367        let mut code_actions_indicator = None;
2368        if let Some(newest_selection_head) = newest_selection_head {
2369            if (start_row..end_row).contains(&newest_selection_head.row()) {
2370                if editor.context_menu_visible() {
2371                    context_menu =
2372                        editor.render_context_menu(newest_selection_head, style.clone(), cx);
2373                }
2374
2375                let active = matches!(
2376                    editor.context_menu,
2377                    Some(crate::ContextMenu::CodeActions(_))
2378                );
2379
2380                code_actions_indicator = editor
2381                    .render_code_actions_indicator(&style, active, cx)
2382                    .map(|indicator| (newest_selection_head.row(), indicator));
2383            }
2384        }
2385
2386        let visible_rows = start_row..start_row + line_layouts.len() as u32;
2387        let mut hover = editor
2388            .hover_state
2389            .render(&snapshot, &style, visible_rows, cx);
2390        let mode = editor.mode;
2391
2392        let mut fold_indicators = editor.render_fold_indicators(
2393            fold_statuses,
2394            &style,
2395            editor.gutter_hovered,
2396            line_height,
2397            gutter_margin,
2398            cx,
2399        );
2400
2401        if let Some((_, context_menu)) = context_menu.as_mut() {
2402            context_menu.layout(
2403                SizeConstraint {
2404                    min: Vector2F::zero(),
2405                    max: vec2f(
2406                        cx.window_size().x() * 0.7,
2407                        (12. * line_height).min((size.y() - line_height) / 2.),
2408                    ),
2409                },
2410                editor,
2411                cx,
2412            );
2413        }
2414
2415        if let Some((_, indicator)) = code_actions_indicator.as_mut() {
2416            indicator.layout(
2417                SizeConstraint::strict_along(
2418                    Axis::Vertical,
2419                    line_height * style.code_actions.vertical_scale,
2420                ),
2421                editor,
2422                cx,
2423            );
2424        }
2425
2426        for fold_indicator in fold_indicators.iter_mut() {
2427            if let Some(indicator) = fold_indicator.as_mut() {
2428                indicator.layout(
2429                    SizeConstraint::strict_along(
2430                        Axis::Vertical,
2431                        line_height * style.code_actions.vertical_scale,
2432                    ),
2433                    editor,
2434                    cx,
2435                );
2436            }
2437        }
2438
2439        if let Some((_, hover_popovers)) = hover.as_mut() {
2440            for hover_popover in hover_popovers.iter_mut() {
2441                hover_popover.layout(
2442                    SizeConstraint {
2443                        min: Vector2F::zero(),
2444                        max: vec2f(
2445                            (120. * em_width) // Default size
2446                                .min(size.x() / 2.) // Shrink to half of the editor width
2447                                .max(MIN_POPOVER_CHARACTER_WIDTH * em_width), // Apply minimum width of 20 characters
2448                            (16. * line_height) // Default size
2449                                .min(size.y() / 2.) // Shrink to half of the editor height
2450                                .max(MIN_POPOVER_LINE_HEIGHT * line_height), // Apply minimum height of 4 lines
2451                        ),
2452                    },
2453                    editor,
2454                    cx,
2455                );
2456            }
2457        }
2458
2459        let invisible_symbol_font_size = self.style.text.font_size / 2.0;
2460        let invisible_symbol_style = RunStyle {
2461            color: self.style.whitespace,
2462            font_id: self.style.text.font_id,
2463            underline: Default::default(),
2464        };
2465
2466        (
2467            size,
2468            LayoutState {
2469                mode,
2470                position_map: Arc::new(PositionMap {
2471                    size,
2472                    scroll_max,
2473                    line_layouts,
2474                    line_height,
2475                    em_width,
2476                    em_advance,
2477                    snapshot,
2478                }),
2479                visible_display_row_range: start_row..end_row,
2480                wrap_guides,
2481                gutter_size,
2482                gutter_padding,
2483                text_size,
2484                scrollbar_row_range,
2485                show_scrollbars,
2486                is_singleton,
2487                max_row,
2488                gutter_margin,
2489                active_rows,
2490                highlighted_rows,
2491                highlighted_ranges,
2492                fold_ranges,
2493                line_number_layouts,
2494                display_hunks,
2495                blocks,
2496                selections,
2497                context_menu,
2498                code_actions_indicator,
2499                fold_indicators,
2500                tab_invisible: cx.text_layout_cache().layout_str(
2501                    "",
2502                    invisible_symbol_font_size,
2503                    &[("".len(), invisible_symbol_style)],
2504                ),
2505                space_invisible: cx.text_layout_cache().layout_str(
2506                    "",
2507                    invisible_symbol_font_size,
2508                    &[("".len(), invisible_symbol_style)],
2509                ),
2510                hover_popovers: hover,
2511            },
2512        )
2513    }
2514
2515    fn paint(
2516        &mut self,
2517        scene: &mut SceneBuilder,
2518        bounds: RectF,
2519        visible_bounds: RectF,
2520        layout: &mut Self::LayoutState,
2521        editor: &mut Editor,
2522        cx: &mut PaintContext<Editor>,
2523    ) -> Self::PaintState {
2524        let visible_bounds = bounds.intersection(visible_bounds).unwrap_or_default();
2525        scene.push_layer(Some(visible_bounds));
2526
2527        let gutter_bounds = RectF::new(bounds.origin(), layout.gutter_size);
2528        let text_bounds = RectF::new(
2529            bounds.origin() + vec2f(layout.gutter_size.x(), 0.0),
2530            layout.text_size,
2531        );
2532
2533        Self::attach_mouse_handlers(
2534            scene,
2535            &layout.position_map,
2536            layout.hover_popovers.is_some(),
2537            visible_bounds,
2538            text_bounds,
2539            gutter_bounds,
2540            bounds,
2541            cx,
2542        );
2543
2544        self.paint_background(scene, gutter_bounds, text_bounds, layout);
2545        if layout.gutter_size.x() > 0. {
2546            self.paint_gutter(scene, gutter_bounds, visible_bounds, layout, editor, cx);
2547        }
2548        self.paint_text(scene, text_bounds, visible_bounds, layout, editor, cx);
2549
2550        scene.push_layer(Some(bounds));
2551        if !layout.blocks.is_empty() {
2552            self.paint_blocks(scene, bounds, visible_bounds, layout, editor, cx);
2553        }
2554        self.paint_scrollbar(scene, bounds, layout, cx, &editor);
2555        scene.pop_layer();
2556
2557        scene.pop_layer();
2558    }
2559
2560    fn rect_for_text_range(
2561        &self,
2562        range_utf16: Range<usize>,
2563        bounds: RectF,
2564        _: RectF,
2565        layout: &Self::LayoutState,
2566        _: &Self::PaintState,
2567        _: &Editor,
2568        _: &ViewContext<Editor>,
2569    ) -> Option<RectF> {
2570        let text_bounds = RectF::new(
2571            bounds.origin() + vec2f(layout.gutter_size.x(), 0.0),
2572            layout.text_size,
2573        );
2574        let content_origin = text_bounds.origin() + vec2f(layout.gutter_margin, 0.);
2575        let scroll_position = layout.position_map.snapshot.scroll_position();
2576        let start_row = scroll_position.y() as u32;
2577        let scroll_top = scroll_position.y() * layout.position_map.line_height;
2578        let scroll_left = scroll_position.x() * layout.position_map.em_width;
2579
2580        let range_start = OffsetUtf16(range_utf16.start)
2581            .to_display_point(&layout.position_map.snapshot.display_snapshot);
2582        if range_start.row() < start_row {
2583            return None;
2584        }
2585
2586        let line = &layout
2587            .position_map
2588            .line_layouts
2589            .get((range_start.row() - start_row) as usize)?
2590            .line;
2591        let range_start_x = line.x_for_index(range_start.column() as usize);
2592        let range_start_y = range_start.row() as f32 * layout.position_map.line_height;
2593        Some(RectF::new(
2594            content_origin
2595                + vec2f(
2596                    range_start_x,
2597                    range_start_y + layout.position_map.line_height,
2598                )
2599                - vec2f(scroll_left, scroll_top),
2600            vec2f(
2601                layout.position_map.em_width,
2602                layout.position_map.line_height,
2603            ),
2604        ))
2605    }
2606
2607    fn debug(
2608        &self,
2609        bounds: RectF,
2610        _: &Self::LayoutState,
2611        _: &Self::PaintState,
2612        _: &Editor,
2613        _: &ViewContext<Editor>,
2614    ) -> json::Value {
2615        json!({
2616            "type": "BufferElement",
2617            "bounds": bounds.to_json()
2618        })
2619    }
2620}
2621
2622type BufferRow = u32;
2623
2624pub struct LayoutState {
2625    position_map: Arc<PositionMap>,
2626    gutter_size: Vector2F,
2627    gutter_padding: f32,
2628    gutter_margin: f32,
2629    text_size: Vector2F,
2630    mode: EditorMode,
2631    wrap_guides: SmallVec<[(f32, bool); 2]>,
2632    visible_display_row_range: Range<u32>,
2633    active_rows: BTreeMap<u32, bool>,
2634    highlighted_rows: Option<Range<u32>>,
2635    line_number_layouts: Vec<Option<text_layout::Line>>,
2636    display_hunks: Vec<DisplayDiffHunk>,
2637    blocks: Vec<BlockLayout>,
2638    highlighted_ranges: Vec<(Range<DisplayPoint>, Color)>,
2639    fold_ranges: Vec<(BufferRow, Range<DisplayPoint>, Color)>,
2640    selections: Vec<(Option<ReplicaId>, Vec<SelectionLayout>)>,
2641    scrollbar_row_range: Range<f32>,
2642    show_scrollbars: bool,
2643    is_singleton: bool,
2644    max_row: u32,
2645    context_menu: Option<(DisplayPoint, AnyElement<Editor>)>,
2646    code_actions_indicator: Option<(u32, AnyElement<Editor>)>,
2647    hover_popovers: Option<(DisplayPoint, Vec<AnyElement<Editor>>)>,
2648    fold_indicators: Vec<Option<AnyElement<Editor>>>,
2649    tab_invisible: Line,
2650    space_invisible: Line,
2651}
2652
2653struct PositionMap {
2654    size: Vector2F,
2655    line_height: f32,
2656    scroll_max: Vector2F,
2657    em_width: f32,
2658    em_advance: f32,
2659    line_layouts: Vec<LineWithInvisibles>,
2660    snapshot: EditorSnapshot,
2661}
2662
2663#[derive(Debug, Copy, Clone)]
2664pub struct PointForPosition {
2665    pub previous_valid: DisplayPoint,
2666    pub next_valid: DisplayPoint,
2667    pub exact_unclipped: DisplayPoint,
2668    pub column_overshoot_after_line_end: u32,
2669}
2670
2671impl PointForPosition {
2672    #[cfg(test)]
2673    pub fn valid(valid: DisplayPoint) -> Self {
2674        Self {
2675            previous_valid: valid,
2676            next_valid: valid,
2677            exact_unclipped: valid,
2678            column_overshoot_after_line_end: 0,
2679        }
2680    }
2681
2682    fn as_valid(&self) -> Option<DisplayPoint> {
2683        if self.previous_valid == self.exact_unclipped && self.next_valid == self.exact_unclipped {
2684            Some(self.previous_valid)
2685        } else {
2686            None
2687        }
2688    }
2689}
2690
2691impl PositionMap {
2692    fn point_for_position(&self, text_bounds: RectF, position: Vector2F) -> PointForPosition {
2693        let scroll_position = self.snapshot.scroll_position();
2694        let position = position - text_bounds.origin();
2695        let y = position.y().max(0.0).min(self.size.y());
2696        let x = position.x() + (scroll_position.x() * self.em_width);
2697        let row = (y / self.line_height + scroll_position.y()) as u32;
2698        let (column, x_overshoot_after_line_end) = if let Some(line) = self
2699            .line_layouts
2700            .get(row as usize - scroll_position.y() as usize)
2701            .map(|line_with_spaces| &line_with_spaces.line)
2702        {
2703            if let Some(ix) = line.index_for_x(x) {
2704                (ix as u32, 0.0)
2705            } else {
2706                (line.len() as u32, 0f32.max(x - line.width()))
2707            }
2708        } else {
2709            (0, x)
2710        };
2711
2712        let mut exact_unclipped = DisplayPoint::new(row, column);
2713        let previous_valid = self.snapshot.clip_point(exact_unclipped, Bias::Left);
2714        let next_valid = self.snapshot.clip_point(exact_unclipped, Bias::Right);
2715
2716        let column_overshoot_after_line_end = (x_overshoot_after_line_end / self.em_advance) as u32;
2717        *exact_unclipped.column_mut() += column_overshoot_after_line_end;
2718        PointForPosition {
2719            previous_valid,
2720            next_valid,
2721            exact_unclipped,
2722            column_overshoot_after_line_end,
2723        }
2724    }
2725}
2726
2727struct BlockLayout {
2728    row: u32,
2729    element: AnyElement<Editor>,
2730    style: BlockStyle,
2731}
2732
2733fn layout_line(
2734    row: u32,
2735    snapshot: &EditorSnapshot,
2736    style: &EditorStyle,
2737    layout_cache: &TextLayoutCache,
2738) -> text_layout::Line {
2739    let mut line = snapshot.line(row);
2740
2741    if line.len() > MAX_LINE_LEN {
2742        let mut len = MAX_LINE_LEN;
2743        while !line.is_char_boundary(len) {
2744            len -= 1;
2745        }
2746
2747        line.truncate(len);
2748    }
2749
2750    layout_cache.layout_str(
2751        &line,
2752        style.text.font_size,
2753        &[(
2754            snapshot.line_len(row) as usize,
2755            RunStyle {
2756                font_id: style.text.font_id,
2757                color: Color::black(),
2758                underline: Default::default(),
2759            },
2760        )],
2761    )
2762}
2763
2764#[derive(Debug)]
2765pub struct Cursor {
2766    origin: Vector2F,
2767    block_width: f32,
2768    line_height: f32,
2769    color: Color,
2770    shape: CursorShape,
2771    block_text: Option<Line>,
2772}
2773
2774impl Cursor {
2775    pub fn new(
2776        origin: Vector2F,
2777        block_width: f32,
2778        line_height: f32,
2779        color: Color,
2780        shape: CursorShape,
2781        block_text: Option<Line>,
2782    ) -> Cursor {
2783        Cursor {
2784            origin,
2785            block_width,
2786            line_height,
2787            color,
2788            shape,
2789            block_text,
2790        }
2791    }
2792
2793    pub fn bounding_rect(&self, origin: Vector2F) -> RectF {
2794        RectF::new(
2795            self.origin + origin,
2796            vec2f(self.block_width, self.line_height),
2797        )
2798    }
2799
2800    pub fn paint(&self, scene: &mut SceneBuilder, origin: Vector2F, cx: &mut WindowContext) {
2801        let bounds = match self.shape {
2802            CursorShape::Bar => RectF::new(self.origin + origin, vec2f(2.0, self.line_height)),
2803            CursorShape::Block | CursorShape::Hollow => RectF::new(
2804                self.origin + origin,
2805                vec2f(self.block_width, self.line_height),
2806            ),
2807            CursorShape::Underscore => RectF::new(
2808                self.origin + origin + Vector2F::new(0.0, self.line_height - 2.0),
2809                vec2f(self.block_width, 2.0),
2810            ),
2811        };
2812
2813        //Draw background or border quad
2814        if matches!(self.shape, CursorShape::Hollow) {
2815            scene.push_quad(Quad {
2816                bounds,
2817                background: None,
2818                border: Border::all(1., self.color),
2819                corner_radii: Default::default(),
2820            });
2821        } else {
2822            scene.push_quad(Quad {
2823                bounds,
2824                background: Some(self.color),
2825                border: Default::default(),
2826                corner_radii: Default::default(),
2827            });
2828        }
2829
2830        if let Some(block_text) = &self.block_text {
2831            block_text.paint(scene, self.origin + origin, bounds, self.line_height, cx);
2832        }
2833    }
2834
2835    pub fn shape(&self) -> CursorShape {
2836        self.shape
2837    }
2838}
2839
2840#[derive(Debug)]
2841pub struct HighlightedRange {
2842    pub start_y: f32,
2843    pub line_height: f32,
2844    pub lines: Vec<HighlightedRangeLine>,
2845    pub color: Color,
2846    pub corner_radius: f32,
2847}
2848
2849#[derive(Debug)]
2850pub struct HighlightedRangeLine {
2851    pub start_x: f32,
2852    pub end_x: f32,
2853}
2854
2855impl HighlightedRange {
2856    pub fn paint(&self, bounds: RectF, scene: &mut SceneBuilder) {
2857        if self.lines.len() >= 2 && self.lines[0].start_x > self.lines[1].end_x {
2858            self.paint_lines(self.start_y, &self.lines[0..1], bounds, scene);
2859            self.paint_lines(
2860                self.start_y + self.line_height,
2861                &self.lines[1..],
2862                bounds,
2863                scene,
2864            );
2865        } else {
2866            self.paint_lines(self.start_y, &self.lines, bounds, scene);
2867        }
2868    }
2869
2870    fn paint_lines(
2871        &self,
2872        start_y: f32,
2873        lines: &[HighlightedRangeLine],
2874        bounds: RectF,
2875        scene: &mut SceneBuilder,
2876    ) {
2877        if lines.is_empty() {
2878            return;
2879        }
2880
2881        let mut path = PathBuilder::new();
2882        let first_line = lines.first().unwrap();
2883        let last_line = lines.last().unwrap();
2884
2885        let first_top_left = vec2f(first_line.start_x, start_y);
2886        let first_top_right = vec2f(first_line.end_x, start_y);
2887
2888        let curve_height = vec2f(0., self.corner_radius);
2889        let curve_width = |start_x: f32, end_x: f32| {
2890            let max = (end_x - start_x) / 2.;
2891            let width = if max < self.corner_radius {
2892                max
2893            } else {
2894                self.corner_radius
2895            };
2896
2897            vec2f(width, 0.)
2898        };
2899
2900        let top_curve_width = curve_width(first_line.start_x, first_line.end_x);
2901        path.reset(first_top_right - top_curve_width);
2902        path.curve_to(first_top_right + curve_height, first_top_right);
2903
2904        let mut iter = lines.iter().enumerate().peekable();
2905        while let Some((ix, line)) = iter.next() {
2906            let bottom_right = vec2f(line.end_x, start_y + (ix + 1) as f32 * self.line_height);
2907
2908            if let Some((_, next_line)) = iter.peek() {
2909                let next_top_right = vec2f(next_line.end_x, bottom_right.y());
2910
2911                match next_top_right.x().partial_cmp(&bottom_right.x()).unwrap() {
2912                    Ordering::Equal => {
2913                        path.line_to(bottom_right);
2914                    }
2915                    Ordering::Less => {
2916                        let curve_width = curve_width(next_top_right.x(), bottom_right.x());
2917                        path.line_to(bottom_right - curve_height);
2918                        if self.corner_radius > 0. {
2919                            path.curve_to(bottom_right - curve_width, bottom_right);
2920                        }
2921                        path.line_to(next_top_right + curve_width);
2922                        if self.corner_radius > 0. {
2923                            path.curve_to(next_top_right + curve_height, next_top_right);
2924                        }
2925                    }
2926                    Ordering::Greater => {
2927                        let curve_width = curve_width(bottom_right.x(), next_top_right.x());
2928                        path.line_to(bottom_right - curve_height);
2929                        if self.corner_radius > 0. {
2930                            path.curve_to(bottom_right + curve_width, bottom_right);
2931                        }
2932                        path.line_to(next_top_right - curve_width);
2933                        if self.corner_radius > 0. {
2934                            path.curve_to(next_top_right + curve_height, next_top_right);
2935                        }
2936                    }
2937                }
2938            } else {
2939                let curve_width = curve_width(line.start_x, line.end_x);
2940                path.line_to(bottom_right - curve_height);
2941                if self.corner_radius > 0. {
2942                    path.curve_to(bottom_right - curve_width, bottom_right);
2943                }
2944
2945                let bottom_left = vec2f(line.start_x, bottom_right.y());
2946                path.line_to(bottom_left + curve_width);
2947                if self.corner_radius > 0. {
2948                    path.curve_to(bottom_left - curve_height, bottom_left);
2949                }
2950            }
2951        }
2952
2953        if first_line.start_x > last_line.start_x {
2954            let curve_width = curve_width(last_line.start_x, first_line.start_x);
2955            let second_top_left = vec2f(last_line.start_x, start_y + self.line_height);
2956            path.line_to(second_top_left + curve_height);
2957            if self.corner_radius > 0. {
2958                path.curve_to(second_top_left + curve_width, second_top_left);
2959            }
2960            let first_bottom_left = vec2f(first_line.start_x, second_top_left.y());
2961            path.line_to(first_bottom_left - curve_width);
2962            if self.corner_radius > 0. {
2963                path.curve_to(first_bottom_left - curve_height, first_bottom_left);
2964            }
2965        }
2966
2967        path.line_to(first_top_left + curve_height);
2968        if self.corner_radius > 0. {
2969            path.curve_to(first_top_left + top_curve_width, first_top_left);
2970        }
2971        path.line_to(first_top_right - top_curve_width);
2972
2973        scene.push_path(path.build(self.color, Some(bounds)));
2974    }
2975}
2976
2977fn range_to_bounds(
2978    range: &Range<DisplayPoint>,
2979    content_origin: Vector2F,
2980    scroll_left: f32,
2981    scroll_top: f32,
2982    visible_row_range: &Range<u32>,
2983    line_end_overshoot: f32,
2984    position_map: &PositionMap,
2985) -> impl Iterator<Item = RectF> {
2986    let mut bounds: SmallVec<[RectF; 1]> = SmallVec::new();
2987
2988    if range.start == range.end {
2989        return bounds.into_iter();
2990    }
2991
2992    let start_row = visible_row_range.start;
2993    let end_row = visible_row_range.end;
2994
2995    let row_range = if range.end.column() == 0 {
2996        cmp::max(range.start.row(), start_row)..cmp::min(range.end.row(), end_row)
2997    } else {
2998        cmp::max(range.start.row(), start_row)..cmp::min(range.end.row() + 1, end_row)
2999    };
3000
3001    let first_y =
3002        content_origin.y() + row_range.start as f32 * position_map.line_height - scroll_top;
3003
3004    for (idx, row) in row_range.enumerate() {
3005        let line_layout = &position_map.line_layouts[(row - start_row) as usize].line;
3006
3007        let start_x = if row == range.start.row() {
3008            content_origin.x() + line_layout.x_for_index(range.start.column() as usize)
3009                - scroll_left
3010        } else {
3011            content_origin.x() - scroll_left
3012        };
3013
3014        let end_x = if row == range.end.row() {
3015            content_origin.x() + line_layout.x_for_index(range.end.column() as usize) - scroll_left
3016        } else {
3017            content_origin.x() + line_layout.width() + line_end_overshoot - scroll_left
3018        };
3019
3020        bounds.push(RectF::from_points(
3021            vec2f(start_x, first_y + position_map.line_height * idx as f32),
3022            vec2f(end_x, first_y + position_map.line_height * (idx + 1) as f32),
3023        ))
3024    }
3025
3026    bounds.into_iter()
3027}
3028
3029pub fn scale_vertical_mouse_autoscroll_delta(delta: f32) -> f32 {
3030    delta.powf(1.5) / 100.0
3031}
3032
3033fn scale_horizontal_mouse_autoscroll_delta(delta: f32) -> f32 {
3034    delta.powf(1.2) / 300.0
3035}
3036
3037#[cfg(test)]
3038mod tests {
3039    use super::*;
3040    use crate::{
3041        display_map::{BlockDisposition, BlockProperties},
3042        editor_tests::{init_test, update_test_language_settings},
3043        Editor, MultiBuffer,
3044    };
3045    use gpui::TestAppContext;
3046    use language::language_settings;
3047    use log::info;
3048    use std::{num::NonZeroU32, sync::Arc};
3049    use util::test::sample_text;
3050
3051    #[gpui::test]
3052    fn test_layout_line_numbers(cx: &mut TestAppContext) {
3053        init_test(cx, |_| {});
3054
3055        let editor = cx
3056            .add_window(|cx| {
3057                let buffer = MultiBuffer::build_simple(&sample_text(6, 6, 'a'), cx);
3058                Editor::new(EditorMode::Full, buffer, None, None, cx)
3059            })
3060            .root(cx);
3061        let element = EditorElement::new(editor.read_with(cx, |editor, cx| editor.style(cx)));
3062
3063        let layouts = editor.update(cx, |editor, cx| {
3064            let snapshot = editor.snapshot(cx);
3065            element
3066                .layout_line_numbers(0..6, &Default::default(), false, &snapshot, cx)
3067                .0
3068        });
3069        assert_eq!(layouts.len(), 6);
3070    }
3071
3072    #[gpui::test]
3073    async fn test_vim_visual_selections(cx: &mut TestAppContext) {
3074        init_test(cx, |_| {});
3075
3076        let editor = cx
3077            .add_window(|cx| {
3078                let buffer = MultiBuffer::build_simple(&(sample_text(6, 6, 'a') + "\n"), cx);
3079                Editor::new(EditorMode::Full, buffer, None, None, cx)
3080            })
3081            .root(cx);
3082        let mut element = EditorElement::new(editor.read_with(cx, |editor, cx| editor.style(cx)));
3083        let (_, state) = editor.update(cx, |editor, cx| {
3084            editor.cursor_shape = CursorShape::Block;
3085            editor.change_selections(None, cx, |s| {
3086                s.select_ranges([
3087                    Point::new(0, 0)..Point::new(1, 0),
3088                    Point::new(3, 2)..Point::new(3, 3),
3089                    Point::new(5, 6)..Point::new(6, 0),
3090                ]);
3091            });
3092            let mut new_parents = Default::default();
3093            let mut notify_views_if_parents_change = Default::default();
3094            let mut layout_cx = LayoutContext::new(
3095                cx,
3096                &mut new_parents,
3097                &mut notify_views_if_parents_change,
3098                false,
3099            );
3100            element.layout(
3101                SizeConstraint::new(vec2f(500., 500.), vec2f(500., 500.)),
3102                editor,
3103                &mut layout_cx,
3104            )
3105        });
3106        assert_eq!(state.selections.len(), 1);
3107        let local_selections = &state.selections[0].1;
3108        assert_eq!(local_selections.len(), 3);
3109        // moves cursor back one line
3110        assert_eq!(local_selections[0].head, DisplayPoint::new(0, 6));
3111        assert_eq!(
3112            local_selections[0].range,
3113            DisplayPoint::new(0, 0)..DisplayPoint::new(1, 0)
3114        );
3115
3116        // moves cursor back one column
3117        assert_eq!(
3118            local_selections[1].range,
3119            DisplayPoint::new(3, 2)..DisplayPoint::new(3, 3)
3120        );
3121        assert_eq!(local_selections[1].head, DisplayPoint::new(3, 2));
3122
3123        // leaves cursor on the max point
3124        assert_eq!(
3125            local_selections[2].range,
3126            DisplayPoint::new(5, 6)..DisplayPoint::new(6, 0)
3127        );
3128        assert_eq!(local_selections[2].head, DisplayPoint::new(6, 0));
3129
3130        // active lines does not include 1 (even though the range of the selection does)
3131        assert_eq!(
3132            state.active_rows.keys().cloned().collect::<Vec<u32>>(),
3133            vec![0, 3, 5, 6]
3134        );
3135
3136        // multi-buffer support
3137        // in DisplayPoint co-ordinates, this is what we're dealing with:
3138        //  0: [[file
3139        //  1:   header]]
3140        //  2: aaaaaa
3141        //  3: bbbbbb
3142        //  4: cccccc
3143        //  5:
3144        //  6: ...
3145        //  7: ffffff
3146        //  8: gggggg
3147        //  9: hhhhhh
3148        // 10:
3149        // 11: [[file
3150        // 12:   header]]
3151        // 13: bbbbbb
3152        // 14: cccccc
3153        // 15: dddddd
3154        let editor = cx
3155            .add_window(|cx| {
3156                let buffer = MultiBuffer::build_multi(
3157                    [
3158                        (
3159                            &(sample_text(8, 6, 'a') + "\n"),
3160                            vec![
3161                                Point::new(0, 0)..Point::new(3, 0),
3162                                Point::new(4, 0)..Point::new(7, 0),
3163                            ],
3164                        ),
3165                        (
3166                            &(sample_text(8, 6, 'a') + "\n"),
3167                            vec![Point::new(1, 0)..Point::new(3, 0)],
3168                        ),
3169                    ],
3170                    cx,
3171                );
3172                Editor::new(EditorMode::Full, buffer, None, None, cx)
3173            })
3174            .root(cx);
3175        let mut element = EditorElement::new(editor.read_with(cx, |editor, cx| editor.style(cx)));
3176        let (_, state) = editor.update(cx, |editor, cx| {
3177            editor.cursor_shape = CursorShape::Block;
3178            editor.change_selections(None, cx, |s| {
3179                s.select_display_ranges([
3180                    DisplayPoint::new(4, 0)..DisplayPoint::new(7, 0),
3181                    DisplayPoint::new(10, 0)..DisplayPoint::new(13, 0),
3182                ]);
3183            });
3184            let mut new_parents = Default::default();
3185            let mut notify_views_if_parents_change = Default::default();
3186            let mut layout_cx = LayoutContext::new(
3187                cx,
3188                &mut new_parents,
3189                &mut notify_views_if_parents_change,
3190                false,
3191            );
3192            element.layout(
3193                SizeConstraint::new(vec2f(500., 500.), vec2f(500., 500.)),
3194                editor,
3195                &mut layout_cx,
3196            )
3197        });
3198
3199        assert_eq!(state.selections.len(), 1);
3200        let local_selections = &state.selections[0].1;
3201        assert_eq!(local_selections.len(), 2);
3202
3203        // moves cursor on excerpt boundary back a line
3204        // and doesn't allow selection to bleed through
3205        assert_eq!(
3206            local_selections[0].range,
3207            DisplayPoint::new(4, 0)..DisplayPoint::new(6, 0)
3208        );
3209        assert_eq!(local_selections[0].head, DisplayPoint::new(5, 0));
3210
3211        // moves cursor on buffer boundary back two lines
3212        // and doesn't allow selection to bleed through
3213        assert_eq!(
3214            local_selections[1].range,
3215            DisplayPoint::new(10, 0)..DisplayPoint::new(11, 0)
3216        );
3217        assert_eq!(local_selections[1].head, DisplayPoint::new(10, 0));
3218    }
3219
3220    #[gpui::test]
3221    fn test_layout_with_placeholder_text_and_blocks(cx: &mut TestAppContext) {
3222        init_test(cx, |_| {});
3223
3224        let editor = cx
3225            .add_window(|cx| {
3226                let buffer = MultiBuffer::build_simple("", cx);
3227                Editor::new(EditorMode::Full, buffer, None, None, cx)
3228            })
3229            .root(cx);
3230
3231        editor.update(cx, |editor, cx| {
3232            editor.set_placeholder_text("hello", cx);
3233            editor.insert_blocks(
3234                [BlockProperties {
3235                    style: BlockStyle::Fixed,
3236                    disposition: BlockDisposition::Above,
3237                    height: 3,
3238                    position: Anchor::min(),
3239                    render: Arc::new(|_| Empty::new().into_any()),
3240                }],
3241                None,
3242                cx,
3243            );
3244
3245            // Blur the editor so that it displays placeholder text.
3246            cx.blur();
3247        });
3248
3249        let mut element = EditorElement::new(editor.read_with(cx, |editor, cx| editor.style(cx)));
3250        let (size, mut state) = editor.update(cx, |editor, cx| {
3251            let mut new_parents = Default::default();
3252            let mut notify_views_if_parents_change = Default::default();
3253            let mut layout_cx = LayoutContext::new(
3254                cx,
3255                &mut new_parents,
3256                &mut notify_views_if_parents_change,
3257                false,
3258            );
3259            element.layout(
3260                SizeConstraint::new(vec2f(500., 500.), vec2f(500., 500.)),
3261                editor,
3262                &mut layout_cx,
3263            )
3264        });
3265
3266        assert_eq!(state.position_map.line_layouts.len(), 4);
3267        assert_eq!(
3268            state
3269                .line_number_layouts
3270                .iter()
3271                .map(Option::is_some)
3272                .collect::<Vec<_>>(),
3273            &[false, false, false, true]
3274        );
3275
3276        // Don't panic.
3277        let mut scene = SceneBuilder::new(1.0);
3278        let bounds = RectF::new(Default::default(), size);
3279        editor.update(cx, |editor, cx| {
3280            element.paint(
3281                &mut scene,
3282                bounds,
3283                bounds,
3284                &mut state,
3285                editor,
3286                &mut PaintContext::new(cx),
3287            );
3288        });
3289    }
3290
3291    #[gpui::test]
3292    fn test_all_invisibles_drawing(cx: &mut TestAppContext) {
3293        const TAB_SIZE: u32 = 4;
3294
3295        let input_text = "\t \t|\t| a b";
3296        let expected_invisibles = vec![
3297            Invisible::Tab {
3298                line_start_offset: 0,
3299            },
3300            Invisible::Whitespace {
3301                line_offset: TAB_SIZE as usize,
3302            },
3303            Invisible::Tab {
3304                line_start_offset: TAB_SIZE as usize + 1,
3305            },
3306            Invisible::Tab {
3307                line_start_offset: TAB_SIZE as usize * 2 + 1,
3308            },
3309            Invisible::Whitespace {
3310                line_offset: TAB_SIZE as usize * 3 + 1,
3311            },
3312            Invisible::Whitespace {
3313                line_offset: TAB_SIZE as usize * 3 + 3,
3314            },
3315        ];
3316        assert_eq!(
3317            expected_invisibles.len(),
3318            input_text
3319                .chars()
3320                .filter(|initial_char| initial_char.is_whitespace())
3321                .count(),
3322            "Hardcoded expected invisibles differ from the actual ones in '{input_text}'"
3323        );
3324
3325        init_test(cx, |s| {
3326            s.defaults.show_whitespaces = Some(ShowWhitespaceSetting::All);
3327            s.defaults.tab_size = NonZeroU32::new(TAB_SIZE);
3328        });
3329
3330        let actual_invisibles =
3331            collect_invisibles_from_new_editor(cx, EditorMode::Full, &input_text, 500.0);
3332
3333        assert_eq!(expected_invisibles, actual_invisibles);
3334    }
3335
3336    #[gpui::test]
3337    fn test_invisibles_dont_appear_in_certain_editors(cx: &mut TestAppContext) {
3338        init_test(cx, |s| {
3339            s.defaults.show_whitespaces = Some(ShowWhitespaceSetting::All);
3340            s.defaults.tab_size = NonZeroU32::new(4);
3341        });
3342
3343        for editor_mode_without_invisibles in [
3344            EditorMode::SingleLine,
3345            EditorMode::AutoHeight { max_lines: 100 },
3346        ] {
3347            let invisibles = collect_invisibles_from_new_editor(
3348                cx,
3349                editor_mode_without_invisibles,
3350                "\t\t\t| | a b",
3351                500.0,
3352            );
3353            assert!(invisibles.is_empty(),
3354                "For editor mode {editor_mode_without_invisibles:?} no invisibles was expected but got {invisibles:?}");
3355        }
3356    }
3357
3358    #[gpui::test]
3359    fn test_wrapped_invisibles_drawing(cx: &mut TestAppContext) {
3360        let tab_size = 4;
3361        let input_text = "a\tbcd   ".repeat(9);
3362        let repeated_invisibles = [
3363            Invisible::Tab {
3364                line_start_offset: 1,
3365            },
3366            Invisible::Whitespace {
3367                line_offset: tab_size as usize + 3,
3368            },
3369            Invisible::Whitespace {
3370                line_offset: tab_size as usize + 4,
3371            },
3372            Invisible::Whitespace {
3373                line_offset: tab_size as usize + 5,
3374            },
3375        ];
3376        let expected_invisibles = std::iter::once(repeated_invisibles)
3377            .cycle()
3378            .take(9)
3379            .flatten()
3380            .collect::<Vec<_>>();
3381        assert_eq!(
3382            expected_invisibles.len(),
3383            input_text
3384                .chars()
3385                .filter(|initial_char| initial_char.is_whitespace())
3386                .count(),
3387            "Hardcoded expected invisibles differ from the actual ones in '{input_text}'"
3388        );
3389        info!("Expected invisibles: {expected_invisibles:?}");
3390
3391        init_test(cx, |_| {});
3392
3393        // Put the same string with repeating whitespace pattern into editors of various size,
3394        // take deliberately small steps during resizing, to put all whitespace kinds near the wrap point.
3395        let resize_step = 10.0;
3396        let mut editor_width = 200.0;
3397        while editor_width <= 1000.0 {
3398            update_test_language_settings(cx, |s| {
3399                s.defaults.tab_size = NonZeroU32::new(tab_size);
3400                s.defaults.show_whitespaces = Some(ShowWhitespaceSetting::All);
3401                s.defaults.preferred_line_length = Some(editor_width as u32);
3402                s.defaults.soft_wrap = Some(language_settings::SoftWrap::PreferredLineLength);
3403            });
3404
3405            let actual_invisibles =
3406                collect_invisibles_from_new_editor(cx, EditorMode::Full, &input_text, editor_width);
3407
3408            // Whatever the editor size is, ensure it has the same invisible kinds in the same order
3409            // (no good guarantees about the offsets: wrapping could trigger padding and its tests should check the offsets).
3410            let mut i = 0;
3411            for (actual_index, actual_invisible) in actual_invisibles.iter().enumerate() {
3412                i = actual_index;
3413                match expected_invisibles.get(i) {
3414                    Some(expected_invisible) => match (expected_invisible, actual_invisible) {
3415                        (Invisible::Whitespace { .. }, Invisible::Whitespace { .. })
3416                        | (Invisible::Tab { .. }, Invisible::Tab { .. }) => {}
3417                        _ => {
3418                            panic!("At index {i}, expected invisible {expected_invisible:?} does not match actual {actual_invisible:?} by kind. Actual invisibles: {actual_invisibles:?}")
3419                        }
3420                    },
3421                    None => panic!("Unexpected extra invisible {actual_invisible:?} at index {i}"),
3422                }
3423            }
3424            let missing_expected_invisibles = &expected_invisibles[i + 1..];
3425            assert!(
3426                missing_expected_invisibles.is_empty(),
3427                "Missing expected invisibles after index {i}: {missing_expected_invisibles:?}"
3428            );
3429
3430            editor_width += resize_step;
3431        }
3432    }
3433
3434    fn collect_invisibles_from_new_editor(
3435        cx: &mut TestAppContext,
3436        editor_mode: EditorMode,
3437        input_text: &str,
3438        editor_width: f32,
3439    ) -> Vec<Invisible> {
3440        info!(
3441            "Creating editor with mode {editor_mode:?}, width {editor_width} and text '{input_text}'"
3442        );
3443        let editor = cx
3444            .add_window(|cx| {
3445                let buffer = MultiBuffer::build_simple(&input_text, cx);
3446                Editor::new(editor_mode, buffer, None, None, cx)
3447            })
3448            .root(cx);
3449
3450        let mut element = EditorElement::new(editor.read_with(cx, |editor, cx| editor.style(cx)));
3451        let (_, layout_state) = editor.update(cx, |editor, cx| {
3452            editor.set_soft_wrap_mode(language_settings::SoftWrap::EditorWidth, cx);
3453            editor.set_wrap_width(Some(editor_width), cx);
3454
3455            let mut new_parents = Default::default();
3456            let mut notify_views_if_parents_change = Default::default();
3457            let mut layout_cx = LayoutContext::new(
3458                cx,
3459                &mut new_parents,
3460                &mut notify_views_if_parents_change,
3461                false,
3462            );
3463            element.layout(
3464                SizeConstraint::new(vec2f(editor_width, 500.), vec2f(editor_width, 500.)),
3465                editor,
3466                &mut layout_cx,
3467            )
3468        });
3469
3470        layout_state
3471            .position_map
3472            .line_layouts
3473            .iter()
3474            .map(|line_with_invisibles| &line_with_invisibles.invisibles)
3475            .flatten()
3476            .cloned()
3477            .collect()
3478    }
3479}