element.rs

   1use super::{
   2    display_map::{BlockContext, ToDisplayPoint},
   3    Anchor, DisplayPoint, Editor, EditorMode, EditorSnapshot, Scroll, Select, SelectPhase,
   4    SoftWrap, ToPoint, MAX_LINE_LEN,
   5};
   6use crate::{
   7    display_map::{BlockStyle, DisplaySnapshot, TransformBlock},
   8    hover_popover::{
   9        HoverAt, HOVER_POPOVER_GAP, MIN_POPOVER_CHARACTER_WIDTH, MIN_POPOVER_LINE_HEIGHT,
  10    },
  11    link_go_to_definition::{
  12        CmdShiftChanged, GoToFetchedDefinition, GoToFetchedTypeDefinition, UpdateGoToDefinitionLink,
  13    },
  14    mouse_context_menu::DeployMouseContextMenu,
  15    AnchorRangeExt, EditorStyle, ToOffset,
  16};
  17use clock::ReplicaId;
  18use collections::{BTreeMap, HashMap};
  19use git::diff::{DiffHunk, DiffHunkStatus};
  20use gpui::{
  21    color::Color,
  22    elements::*,
  23    fonts::{HighlightStyle, Underline},
  24    geometry::{
  25        rect::RectF,
  26        vector::{vec2f, Vector2F},
  27        PathBuilder,
  28    },
  29    json::{self, ToJson},
  30    platform::CursorStyle,
  31    text_layout::{self, Line, RunStyle, TextLayoutCache},
  32    AppContext, Axis, Border, CursorRegion, Element, ElementBox, Event, EventContext,
  33    LayoutContext, ModifiersChangedEvent, MouseButton, MouseButtonEvent, MouseMovedEvent,
  34    MouseRegion, MutableAppContext, PaintContext, Quad, Scene, SizeConstraint, ViewContext,
  35    WeakViewHandle,
  36};
  37use json::json;
  38use language::{Bias, DiagnosticSeverity, OffsetUtf16, Point, Selection};
  39use project::ProjectPath;
  40use settings::{GitGutter, Settings};
  41use smallvec::SmallVec;
  42use std::{
  43    cmp::{self, Ordering},
  44    fmt::Write,
  45    iter,
  46    ops::Range,
  47    sync::Arc,
  48};
  49use theme::DiffStyle;
  50
  51#[derive(Debug)]
  52struct DiffHunkLayout {
  53    visual_range: Range<u32>,
  54    status: DiffHunkStatus,
  55    is_folded: bool,
  56}
  57
  58struct SelectionLayout {
  59    head: DisplayPoint,
  60    range: Range<DisplayPoint>,
  61}
  62
  63impl SelectionLayout {
  64    fn new<T: ToPoint + ToDisplayPoint + Clone>(
  65        selection: Selection<T>,
  66        line_mode: bool,
  67        map: &DisplaySnapshot,
  68    ) -> Self {
  69        if line_mode {
  70            let selection = selection.map(|p| p.to_point(&map.buffer_snapshot));
  71            let point_range = map.expand_to_line(selection.range());
  72            Self {
  73                head: selection.head().to_display_point(map),
  74                range: point_range.start.to_display_point(map)
  75                    ..point_range.end.to_display_point(map),
  76            }
  77        } else {
  78            let selection = selection.map(|p| p.to_display_point(map));
  79            Self {
  80                head: selection.head(),
  81                range: selection.range(),
  82            }
  83        }
  84    }
  85}
  86
  87#[derive(Clone)]
  88pub struct EditorElement {
  89    view: WeakViewHandle<Editor>,
  90    style: Arc<EditorStyle>,
  91    cursor_shape: CursorShape,
  92}
  93
  94impl EditorElement {
  95    pub fn new(
  96        view: WeakViewHandle<Editor>,
  97        style: EditorStyle,
  98        cursor_shape: CursorShape,
  99    ) -> Self {
 100        Self {
 101            view,
 102            style: Arc::new(style),
 103            cursor_shape,
 104        }
 105    }
 106
 107    fn view<'a>(&self, cx: &'a AppContext) -> &'a Editor {
 108        self.view.upgrade(cx).unwrap().read(cx)
 109    }
 110
 111    fn update_view<F, T>(&self, cx: &mut MutableAppContext, f: F) -> T
 112    where
 113        F: FnOnce(&mut Editor, &mut ViewContext<Editor>) -> T,
 114    {
 115        self.view.upgrade(cx).unwrap().update(cx, f)
 116    }
 117
 118    fn snapshot(&self, cx: &mut MutableAppContext) -> EditorSnapshot {
 119        self.update_view(cx, |view, cx| view.snapshot(cx))
 120    }
 121
 122    fn attach_mouse_handlers(
 123        view: &WeakViewHandle<Editor>,
 124        position_map: &Arc<PositionMap>,
 125        visible_bounds: RectF,
 126        text_bounds: RectF,
 127        gutter_bounds: RectF,
 128        bounds: RectF,
 129        cx: &mut PaintContext,
 130    ) {
 131        enum EditorElementMouseHandlers {}
 132        cx.scene.push_mouse_region(
 133            MouseRegion::new::<EditorElementMouseHandlers>(view.id(), view.id(), visible_bounds)
 134                .on_down(MouseButton::Left, {
 135                    let position_map = position_map.clone();
 136                    move |e, cx| {
 137                        if !Self::mouse_down(
 138                            e.platform_event,
 139                            position_map.as_ref(),
 140                            text_bounds,
 141                            gutter_bounds,
 142                            cx,
 143                        ) {
 144                            cx.propogate_event();
 145                        }
 146                    }
 147                })
 148                .on_down(MouseButton::Right, {
 149                    let position_map = position_map.clone();
 150                    move |e, cx| {
 151                        if !Self::mouse_right_down(
 152                            e.position,
 153                            position_map.as_ref(),
 154                            text_bounds,
 155                            cx,
 156                        ) {
 157                            cx.propogate_event();
 158                        }
 159                    }
 160                })
 161                .on_up(MouseButton::Left, {
 162                    let view = view.clone();
 163                    let position_map = position_map.clone();
 164                    move |e, cx| {
 165                        if !Self::mouse_up(
 166                            view.clone(),
 167                            e.position,
 168                            e.cmd,
 169                            e.shift,
 170                            position_map.as_ref(),
 171                            text_bounds,
 172                            cx,
 173                        ) {
 174                            cx.propogate_event()
 175                        }
 176                    }
 177                })
 178                .on_drag(MouseButton::Left, {
 179                    let view = view.clone();
 180                    let position_map = position_map.clone();
 181                    move |e, cx| {
 182                        if !Self::mouse_dragged(
 183                            view.clone(),
 184                            e.platform_event,
 185                            position_map.as_ref(),
 186                            text_bounds,
 187                            cx,
 188                        ) {
 189                            cx.propogate_event()
 190                        }
 191                    }
 192                })
 193                .on_move({
 194                    let position_map = position_map.clone();
 195                    move |e, cx| {
 196                        if !Self::mouse_moved(e.platform_event, &position_map, text_bounds, cx) {
 197                            cx.propogate_event()
 198                        }
 199                    }
 200                })
 201                .on_scroll({
 202                    let position_map = position_map.clone();
 203                    move |e, cx| {
 204                        if !Self::scroll(e.position, e.delta, e.precise, &position_map, bounds, cx)
 205                        {
 206                            cx.propogate_event()
 207                        }
 208                    }
 209                }),
 210        );
 211    }
 212
 213    fn mouse_down(
 214        MouseButtonEvent {
 215            position,
 216            ctrl,
 217            alt,
 218            shift,
 219            cmd,
 220            mut click_count,
 221            ..
 222        }: MouseButtonEvent,
 223        position_map: &PositionMap,
 224        text_bounds: RectF,
 225        gutter_bounds: RectF,
 226        cx: &mut EventContext,
 227    ) -> bool {
 228        if gutter_bounds.contains_point(position) {
 229            click_count = 3; // Simulate triple-click when clicking the gutter to select lines
 230        } else if !text_bounds.contains_point(position) {
 231            return false;
 232        }
 233
 234        let (position, target_position) = position_map.point_for_position(text_bounds, position);
 235
 236        if shift && alt {
 237            cx.dispatch_action(Select(SelectPhase::BeginColumnar {
 238                position,
 239                goal_column: target_position.column(),
 240            }));
 241        } else if shift && !ctrl && !alt && !cmd {
 242            cx.dispatch_action(Select(SelectPhase::Extend {
 243                position,
 244                click_count,
 245            }));
 246        } else {
 247            cx.dispatch_action(Select(SelectPhase::Begin {
 248                position,
 249                add: alt,
 250                click_count,
 251            }));
 252        }
 253
 254        true
 255    }
 256
 257    fn mouse_right_down(
 258        position: Vector2F,
 259        position_map: &PositionMap,
 260        text_bounds: RectF,
 261        cx: &mut EventContext,
 262    ) -> bool {
 263        if !text_bounds.contains_point(position) {
 264            return false;
 265        }
 266
 267        let (point, _) = position_map.point_for_position(text_bounds, position);
 268
 269        cx.dispatch_action(DeployMouseContextMenu { position, point });
 270        true
 271    }
 272
 273    fn mouse_up(
 274        view: WeakViewHandle<Editor>,
 275        position: Vector2F,
 276        cmd: bool,
 277        shift: bool,
 278        position_map: &PositionMap,
 279        text_bounds: RectF,
 280        cx: &mut EventContext,
 281    ) -> bool {
 282        let view = view.upgrade(cx.app).unwrap().read(cx.app);
 283        let end_selection = view.has_pending_selection();
 284        let pending_nonempty_selections = view.has_pending_nonempty_selection();
 285
 286        if end_selection {
 287            cx.dispatch_action(Select(SelectPhase::End));
 288        }
 289
 290        if !pending_nonempty_selections && cmd && text_bounds.contains_point(position) {
 291            let (point, target_point) = position_map.point_for_position(text_bounds, position);
 292
 293            if point == target_point {
 294                if shift {
 295                    cx.dispatch_action(GoToFetchedTypeDefinition { point });
 296                } else {
 297                    cx.dispatch_action(GoToFetchedDefinition { point });
 298                }
 299
 300                return true;
 301            }
 302        }
 303
 304        end_selection
 305    }
 306
 307    fn mouse_dragged(
 308        view: WeakViewHandle<Editor>,
 309        MouseMovedEvent {
 310            cmd,
 311            shift,
 312            position,
 313            ..
 314        }: MouseMovedEvent,
 315        position_map: &PositionMap,
 316        text_bounds: RectF,
 317        cx: &mut EventContext,
 318    ) -> bool {
 319        // This will be handled more correctly once https://github.com/zed-industries/zed/issues/1218 is completed
 320        // Don't trigger hover popover if mouse is hovering over context menu
 321        let point = if text_bounds.contains_point(position) {
 322            let (point, target_point) = position_map.point_for_position(text_bounds, position);
 323            if point == target_point {
 324                Some(point)
 325            } else {
 326                None
 327            }
 328        } else {
 329            None
 330        };
 331
 332        cx.dispatch_action(UpdateGoToDefinitionLink {
 333            point,
 334            cmd_held: cmd,
 335            shift_held: shift,
 336        });
 337
 338        let view = view.upgrade(cx.app).unwrap().read(cx.app);
 339        if view.has_pending_selection() {
 340            let mut scroll_delta = Vector2F::zero();
 341
 342            let vertical_margin = position_map.line_height.min(text_bounds.height() / 3.0);
 343            let top = text_bounds.origin_y() + vertical_margin;
 344            let bottom = text_bounds.lower_left().y() - vertical_margin;
 345            if position.y() < top {
 346                scroll_delta.set_y(-scale_vertical_mouse_autoscroll_delta(top - position.y()))
 347            }
 348            if position.y() > bottom {
 349                scroll_delta.set_y(scale_vertical_mouse_autoscroll_delta(position.y() - bottom))
 350            }
 351
 352            let horizontal_margin = position_map.line_height.min(text_bounds.width() / 3.0);
 353            let left = text_bounds.origin_x() + horizontal_margin;
 354            let right = text_bounds.upper_right().x() - horizontal_margin;
 355            if position.x() < left {
 356                scroll_delta.set_x(-scale_horizontal_mouse_autoscroll_delta(
 357                    left - position.x(),
 358                ))
 359            }
 360            if position.x() > right {
 361                scroll_delta.set_x(scale_horizontal_mouse_autoscroll_delta(
 362                    position.x() - right,
 363                ))
 364            }
 365
 366            let (position, target_position) =
 367                position_map.point_for_position(text_bounds, position);
 368
 369            cx.dispatch_action(Select(SelectPhase::Update {
 370                position,
 371                goal_column: target_position.column(),
 372                scroll_position: (position_map.snapshot.scroll_position() + scroll_delta)
 373                    .clamp(Vector2F::zero(), position_map.scroll_max),
 374            }));
 375
 376            cx.dispatch_action(HoverAt { point });
 377            true
 378        } else {
 379            cx.dispatch_action(HoverAt { point });
 380            false
 381        }
 382    }
 383
 384    fn mouse_moved(
 385        MouseMovedEvent {
 386            cmd,
 387            shift,
 388            position,
 389            ..
 390        }: MouseMovedEvent,
 391        position_map: &PositionMap,
 392        text_bounds: RectF,
 393        cx: &mut EventContext,
 394    ) -> bool {
 395        // This will be handled more correctly once https://github.com/zed-industries/zed/issues/1218 is completed
 396        // Don't trigger hover popover if mouse is hovering over context menu
 397        let point = if text_bounds.contains_point(position) {
 398            let (point, target_point) = position_map.point_for_position(text_bounds, position);
 399            if point == target_point {
 400                Some(point)
 401            } else {
 402                None
 403            }
 404        } else {
 405            None
 406        };
 407
 408        cx.dispatch_action(UpdateGoToDefinitionLink {
 409            point,
 410            cmd_held: cmd,
 411            shift_held: shift,
 412        });
 413
 414        cx.dispatch_action(HoverAt { point });
 415        true
 416    }
 417
 418    fn modifiers_changed(&self, event: ModifiersChangedEvent, cx: &mut EventContext) -> bool {
 419        cx.dispatch_action(CmdShiftChanged {
 420            cmd_down: event.cmd,
 421            shift_down: event.shift,
 422        });
 423        false
 424    }
 425
 426    fn scroll(
 427        position: Vector2F,
 428        mut delta: Vector2F,
 429        precise: bool,
 430        position_map: &PositionMap,
 431        bounds: RectF,
 432        cx: &mut EventContext,
 433    ) -> bool {
 434        if !bounds.contains_point(position) {
 435            return false;
 436        }
 437
 438        let max_glyph_width = position_map.em_width;
 439        if !precise {
 440            delta *= vec2f(max_glyph_width, position_map.line_height);
 441        }
 442
 443        let scroll_position = position_map.snapshot.scroll_position();
 444        let x = (scroll_position.x() * max_glyph_width - delta.x()) / max_glyph_width;
 445        let y =
 446            (scroll_position.y() * position_map.line_height - delta.y()) / position_map.line_height;
 447        let scroll_position = vec2f(x, y).clamp(Vector2F::zero(), position_map.scroll_max);
 448
 449        cx.dispatch_action(Scroll(scroll_position));
 450
 451        true
 452    }
 453
 454    fn paint_background(
 455        &self,
 456        gutter_bounds: RectF,
 457        text_bounds: RectF,
 458        layout: &LayoutState,
 459        cx: &mut PaintContext,
 460    ) {
 461        let bounds = gutter_bounds.union_rect(text_bounds);
 462        let scroll_top =
 463            layout.position_map.snapshot.scroll_position().y() * layout.position_map.line_height;
 464        let editor = self.view(cx.app);
 465        cx.scene.push_quad(Quad {
 466            bounds: gutter_bounds,
 467            background: Some(self.style.gutter_background),
 468            border: Border::new(0., Color::transparent_black()),
 469            corner_radius: 0.,
 470        });
 471        cx.scene.push_quad(Quad {
 472            bounds: text_bounds,
 473            background: Some(self.style.background),
 474            border: Border::new(0., Color::transparent_black()),
 475            corner_radius: 0.,
 476        });
 477
 478        if let EditorMode::Full = editor.mode {
 479            let mut active_rows = layout.active_rows.iter().peekable();
 480            while let Some((start_row, contains_non_empty_selection)) = active_rows.next() {
 481                let mut end_row = *start_row;
 482                while active_rows.peek().map_or(false, |r| {
 483                    *r.0 == end_row + 1 && r.1 == contains_non_empty_selection
 484                }) {
 485                    active_rows.next().unwrap();
 486                    end_row += 1;
 487                }
 488
 489                if !contains_non_empty_selection {
 490                    let origin = vec2f(
 491                        bounds.origin_x(),
 492                        bounds.origin_y() + (layout.position_map.line_height * *start_row as f32)
 493                            - scroll_top,
 494                    );
 495                    let size = vec2f(
 496                        bounds.width(),
 497                        layout.position_map.line_height * (end_row - start_row + 1) as f32,
 498                    );
 499                    cx.scene.push_quad(Quad {
 500                        bounds: RectF::new(origin, size),
 501                        background: Some(self.style.active_line_background),
 502                        border: Border::default(),
 503                        corner_radius: 0.,
 504                    });
 505                }
 506            }
 507
 508            if let Some(highlighted_rows) = &layout.highlighted_rows {
 509                let origin = vec2f(
 510                    bounds.origin_x(),
 511                    bounds.origin_y()
 512                        + (layout.position_map.line_height * highlighted_rows.start as f32)
 513                        - scroll_top,
 514                );
 515                let size = vec2f(
 516                    bounds.width(),
 517                    layout.position_map.line_height * highlighted_rows.len() as f32,
 518                );
 519                cx.scene.push_quad(Quad {
 520                    bounds: RectF::new(origin, size),
 521                    background: Some(self.style.highlighted_line_background),
 522                    border: Border::default(),
 523                    corner_radius: 0.,
 524                });
 525            }
 526        }
 527    }
 528
 529    fn paint_gutter(
 530        &mut self,
 531        bounds: RectF,
 532        visible_bounds: RectF,
 533        layout: &mut LayoutState,
 534        cx: &mut PaintContext,
 535    ) {
 536        struct GutterLayout {
 537            line_height: f32,
 538            // scroll_position: Vector2F,
 539            scroll_top: f32,
 540            bounds: RectF,
 541        }
 542
 543        fn diff_quad(
 544            hunk: &DiffHunkLayout,
 545            gutter_layout: &GutterLayout,
 546            diff_style: &DiffStyle,
 547        ) -> Quad {
 548            let color = match (hunk.status, hunk.is_folded) {
 549                (DiffHunkStatus::Added, false) => diff_style.inserted,
 550                (DiffHunkStatus::Modified, false) => diff_style.modified,
 551
 552                //TODO: This rendering is entirely a horrible hack
 553                (DiffHunkStatus::Removed, false) => {
 554                    let row = hunk.visual_range.start;
 555
 556                    let offset = gutter_layout.line_height / 2.;
 557                    let start_y =
 558                        row as f32 * gutter_layout.line_height - offset - gutter_layout.scroll_top;
 559                    let end_y = start_y + gutter_layout.line_height;
 560
 561                    let width = diff_style.removed_width_em * gutter_layout.line_height;
 562                    let highlight_origin = gutter_layout.bounds.origin() + vec2f(-width, start_y);
 563                    let highlight_size = vec2f(width * 2., end_y - start_y);
 564                    let highlight_bounds = RectF::new(highlight_origin, highlight_size);
 565
 566                    return Quad {
 567                        bounds: highlight_bounds,
 568                        background: Some(diff_style.deleted),
 569                        border: Border::new(0., Color::transparent_black()),
 570                        corner_radius: 1. * gutter_layout.line_height,
 571                    };
 572                }
 573
 574                (_, true) => {
 575                    let row = hunk.visual_range.start;
 576                    let start_y = row as f32 * gutter_layout.line_height - gutter_layout.scroll_top;
 577                    let end_y = start_y + gutter_layout.line_height;
 578
 579                    let width = diff_style.removed_width_em * gutter_layout.line_height;
 580                    let highlight_origin = gutter_layout.bounds.origin() + vec2f(-width, start_y);
 581                    let highlight_size = vec2f(width * 2., end_y - start_y);
 582                    let highlight_bounds = RectF::new(highlight_origin, highlight_size);
 583
 584                    return Quad {
 585                        bounds: highlight_bounds,
 586                        background: Some(diff_style.modified),
 587                        border: Border::new(0., Color::transparent_black()),
 588                        corner_radius: 1. * gutter_layout.line_height,
 589                    };
 590                }
 591            };
 592
 593            let start_row = hunk.visual_range.start;
 594            let end_row = hunk.visual_range.end;
 595
 596            let start_y = start_row as f32 * gutter_layout.line_height - gutter_layout.scroll_top;
 597            let end_y = end_row as f32 * gutter_layout.line_height - gutter_layout.scroll_top;
 598
 599            let width = diff_style.width_em * gutter_layout.line_height;
 600            let highlight_origin = gutter_layout.bounds.origin() + vec2f(-width, start_y);
 601            let highlight_size = vec2f(width * 2., end_y - start_y);
 602            let highlight_bounds = RectF::new(highlight_origin, highlight_size);
 603
 604            Quad {
 605                bounds: highlight_bounds,
 606                background: Some(color),
 607                border: Border::new(0., Color::transparent_black()),
 608                corner_radius: diff_style.corner_radius * gutter_layout.line_height,
 609            }
 610        }
 611
 612        let scroll_position = layout.position_map.snapshot.scroll_position();
 613        let gutter_layout = {
 614            let line_height = layout.position_map.line_height;
 615            GutterLayout {
 616                scroll_top: scroll_position.y() * line_height,
 617                line_height,
 618                bounds,
 619            }
 620        };
 621
 622        let diff_style = &cx.global::<Settings>().theme.editor.diff.clone();
 623        let show_gutter = matches!(
 624            &cx.global::<Settings>()
 625                .git_overrides
 626                .git_gutter
 627                .unwrap_or_default(),
 628            GitGutter::TrackedFiles
 629        );
 630
 631        if show_gutter {
 632            for hunk in &layout.hunk_layouts {
 633                let quad = diff_quad(hunk, &gutter_layout, diff_style);
 634                cx.scene.push_quad(quad);
 635            }
 636        }
 637
 638        for (ix, line) in layout.line_number_layouts.iter().enumerate() {
 639            if let Some(line) = line {
 640                let line_origin = bounds.origin()
 641                    + vec2f(
 642                        bounds.width() - line.width() - layout.gutter_padding,
 643                        ix as f32 * gutter_layout.line_height
 644                            - (gutter_layout.scroll_top % gutter_layout.line_height),
 645                    );
 646
 647                line.paint(line_origin, visible_bounds, gutter_layout.line_height, cx);
 648            }
 649        }
 650
 651        if let Some((row, indicator)) = layout.code_actions_indicator.as_mut() {
 652            let mut x = bounds.width() - layout.gutter_padding;
 653            let mut y = *row as f32 * gutter_layout.line_height - gutter_layout.scroll_top;
 654            x += ((layout.gutter_padding + layout.gutter_margin) - indicator.size().x()) / 2.;
 655            y += (gutter_layout.line_height - indicator.size().y()) / 2.;
 656            indicator.paint(bounds.origin() + vec2f(x, y), visible_bounds, cx);
 657        }
 658    }
 659
 660    fn paint_text(
 661        &mut self,
 662        bounds: RectF,
 663        visible_bounds: RectF,
 664        layout: &mut LayoutState,
 665        cx: &mut PaintContext,
 666    ) {
 667        let view = self.view(cx.app);
 668        let style = &self.style;
 669        let local_replica_id = view.replica_id(cx);
 670        let scroll_position = layout.position_map.snapshot.scroll_position();
 671        let start_row = scroll_position.y() as u32;
 672        let scroll_top = scroll_position.y() * layout.position_map.line_height;
 673        let end_row =
 674            ((scroll_top + bounds.height()) / layout.position_map.line_height).ceil() as u32 + 1; // Add 1 to ensure selections bleed off screen
 675        let max_glyph_width = layout.position_map.em_width;
 676        let scroll_left = scroll_position.x() * max_glyph_width;
 677        let content_origin = bounds.origin() + vec2f(layout.gutter_margin, 0.);
 678
 679        cx.scene.push_layer(Some(bounds));
 680
 681        cx.scene.push_cursor_region(CursorRegion {
 682            bounds,
 683            style: if !view.link_go_to_definition_state.definitions.is_empty() {
 684                CursorStyle::PointingHand
 685            } else {
 686                CursorStyle::IBeam
 687            },
 688        });
 689
 690        for (range, color) in &layout.highlighted_ranges {
 691            self.paint_highlighted_range(
 692                range.clone(),
 693                start_row,
 694                end_row,
 695                *color,
 696                0.,
 697                0.15 * layout.position_map.line_height,
 698                layout,
 699                content_origin,
 700                scroll_top,
 701                scroll_left,
 702                bounds,
 703                cx,
 704            );
 705        }
 706
 707        let mut cursors = SmallVec::<[Cursor; 32]>::new();
 708        for (replica_id, selections) in &layout.selections {
 709            let selection_style = style.replica_selection_style(*replica_id);
 710            let corner_radius = 0.15 * layout.position_map.line_height;
 711
 712            for selection in selections {
 713                self.paint_highlighted_range(
 714                    selection.range.clone(),
 715                    start_row,
 716                    end_row,
 717                    selection_style.selection,
 718                    corner_radius,
 719                    corner_radius * 2.,
 720                    layout,
 721                    content_origin,
 722                    scroll_top,
 723                    scroll_left,
 724                    bounds,
 725                    cx,
 726                );
 727
 728                if view.show_local_cursors() || *replica_id != local_replica_id {
 729                    let cursor_position = selection.head;
 730                    if (start_row..end_row).contains(&cursor_position.row()) {
 731                        let cursor_row_layout = &layout.position_map.line_layouts
 732                            [(cursor_position.row() - start_row) as usize];
 733                        let cursor_column = cursor_position.column() as usize;
 734
 735                        let cursor_character_x = cursor_row_layout.x_for_index(cursor_column);
 736                        let mut block_width =
 737                            cursor_row_layout.x_for_index(cursor_column + 1) - cursor_character_x;
 738                        if block_width == 0.0 {
 739                            block_width = layout.position_map.em_width;
 740                        }
 741                        let block_text = if let CursorShape::Block = self.cursor_shape {
 742                            layout
 743                                .position_map
 744                                .snapshot
 745                                .chars_at(cursor_position)
 746                                .next()
 747                                .and_then(|character| {
 748                                    let font_id =
 749                                        cursor_row_layout.font_for_index(cursor_column)?;
 750                                    let text = character.to_string();
 751
 752                                    Some(cx.text_layout_cache.layout_str(
 753                                        &text,
 754                                        cursor_row_layout.font_size(),
 755                                        &[(
 756                                            text.len(),
 757                                            RunStyle {
 758                                                font_id,
 759                                                color: style.background,
 760                                                underline: Default::default(),
 761                                            },
 762                                        )],
 763                                    ))
 764                                })
 765                        } else {
 766                            None
 767                        };
 768
 769                        let x = cursor_character_x - scroll_left;
 770                        let y = cursor_position.row() as f32 * layout.position_map.line_height
 771                            - scroll_top;
 772                        cursors.push(Cursor {
 773                            color: selection_style.cursor,
 774                            block_width,
 775                            origin: vec2f(x, y),
 776                            line_height: layout.position_map.line_height,
 777                            shape: self.cursor_shape,
 778                            block_text,
 779                        });
 780                    }
 781                }
 782            }
 783        }
 784
 785        if let Some(visible_text_bounds) = bounds.intersection(visible_bounds) {
 786            // Draw glyphs
 787            for (ix, line) in layout.position_map.line_layouts.iter().enumerate() {
 788                let row = start_row + ix as u32;
 789                line.paint(
 790                    content_origin
 791                        + vec2f(
 792                            -scroll_left,
 793                            row as f32 * layout.position_map.line_height - scroll_top,
 794                        ),
 795                    visible_text_bounds,
 796                    layout.position_map.line_height,
 797                    cx,
 798                );
 799            }
 800        }
 801
 802        cx.scene.push_layer(Some(bounds));
 803        for cursor in cursors {
 804            cursor.paint(content_origin, cx);
 805        }
 806        cx.scene.pop_layer();
 807
 808        if let Some((position, context_menu)) = layout.context_menu.as_mut() {
 809            cx.scene.push_stacking_context(None);
 810            let cursor_row_layout =
 811                &layout.position_map.line_layouts[(position.row() - start_row) as usize];
 812            let x = cursor_row_layout.x_for_index(position.column() as usize) - scroll_left;
 813            let y = (position.row() + 1) as f32 * layout.position_map.line_height - scroll_top;
 814            let mut list_origin = content_origin + vec2f(x, y);
 815            let list_width = context_menu.size().x();
 816            let list_height = context_menu.size().y();
 817
 818            // Snap the right edge of the list to the right edge of the window if
 819            // its horizontal bounds overflow.
 820            if list_origin.x() + list_width > cx.window_size.x() {
 821                list_origin.set_x((cx.window_size.x() - list_width).max(0.));
 822            }
 823
 824            if list_origin.y() + list_height > bounds.max_y() {
 825                list_origin.set_y(list_origin.y() - layout.position_map.line_height - list_height);
 826            }
 827
 828            context_menu.paint(
 829                list_origin,
 830                RectF::from_points(Vector2F::zero(), vec2f(f32::MAX, f32::MAX)), // Let content bleed outside of editor
 831                cx,
 832            );
 833
 834            cx.scene.pop_stacking_context();
 835        }
 836
 837        if let Some((position, hover_popovers)) = layout.hover_popovers.as_mut() {
 838            cx.scene.push_stacking_context(None);
 839
 840            // This is safe because we check on layout whether the required row is available
 841            let hovered_row_layout =
 842                &layout.position_map.line_layouts[(position.row() - start_row) as usize];
 843
 844            // Minimum required size: Take the first popover, and add 1.5 times the minimum popover
 845            // height. This is the size we will use to decide whether to render popovers above or below
 846            // the hovered line.
 847            let first_size = hover_popovers[0].size();
 848            let height_to_reserve = first_size.y()
 849                + 1.5 * MIN_POPOVER_LINE_HEIGHT as f32 * layout.position_map.line_height;
 850
 851            // Compute Hovered Point
 852            let x = hovered_row_layout.x_for_index(position.column() as usize) - scroll_left;
 853            let y = position.row() as f32 * layout.position_map.line_height - scroll_top;
 854            let hovered_point = content_origin + vec2f(x, y);
 855
 856            if hovered_point.y() - height_to_reserve > 0.0 {
 857                // There is enough space above. Render popovers above the hovered point
 858                let mut current_y = hovered_point.y();
 859                for hover_popover in hover_popovers {
 860                    let size = hover_popover.size();
 861                    let mut popover_origin = vec2f(hovered_point.x(), current_y - size.y());
 862
 863                    let x_out_of_bounds = bounds.max_x() - (popover_origin.x() + size.x());
 864                    if x_out_of_bounds < 0.0 {
 865                        popover_origin.set_x(popover_origin.x() + x_out_of_bounds);
 866                    }
 867
 868                    hover_popover.paint(
 869                        popover_origin,
 870                        RectF::from_points(Vector2F::zero(), vec2f(f32::MAX, f32::MAX)), // Let content bleed outside of editor
 871                        cx,
 872                    );
 873
 874                    current_y = popover_origin.y() - HOVER_POPOVER_GAP;
 875                }
 876            } else {
 877                // There is not enough space above. Render popovers below the hovered point
 878                let mut current_y = hovered_point.y() + layout.position_map.line_height;
 879                for hover_popover in hover_popovers {
 880                    let size = hover_popover.size();
 881                    let mut popover_origin = vec2f(hovered_point.x(), current_y);
 882
 883                    let x_out_of_bounds = bounds.max_x() - (popover_origin.x() + size.x());
 884                    if x_out_of_bounds < 0.0 {
 885                        popover_origin.set_x(popover_origin.x() + x_out_of_bounds);
 886                    }
 887
 888                    hover_popover.paint(
 889                        popover_origin,
 890                        RectF::from_points(Vector2F::zero(), vec2f(f32::MAX, f32::MAX)), // Let content bleed outside of editor
 891                        cx,
 892                    );
 893
 894                    current_y = popover_origin.y() + size.y() + HOVER_POPOVER_GAP;
 895                }
 896            }
 897
 898            cx.scene.pop_stacking_context();
 899        }
 900
 901        cx.scene.pop_layer();
 902    }
 903
 904    #[allow(clippy::too_many_arguments)]
 905    fn paint_highlighted_range(
 906        &self,
 907        range: Range<DisplayPoint>,
 908        start_row: u32,
 909        end_row: u32,
 910        color: Color,
 911        corner_radius: f32,
 912        line_end_overshoot: f32,
 913        layout: &LayoutState,
 914        content_origin: Vector2F,
 915        scroll_top: f32,
 916        scroll_left: f32,
 917        bounds: RectF,
 918        cx: &mut PaintContext,
 919    ) {
 920        if range.start != range.end {
 921            let row_range = if range.end.column() == 0 {
 922                cmp::max(range.start.row(), start_row)..cmp::min(range.end.row(), end_row)
 923            } else {
 924                cmp::max(range.start.row(), start_row)..cmp::min(range.end.row() + 1, end_row)
 925            };
 926
 927            let highlighted_range = HighlightedRange {
 928                color,
 929                line_height: layout.position_map.line_height,
 930                corner_radius,
 931                start_y: content_origin.y()
 932                    + row_range.start as f32 * layout.position_map.line_height
 933                    - scroll_top,
 934                lines: row_range
 935                    .into_iter()
 936                    .map(|row| {
 937                        let line_layout =
 938                            &layout.position_map.line_layouts[(row - start_row) as usize];
 939                        HighlightedRangeLine {
 940                            start_x: if row == range.start.row() {
 941                                content_origin.x()
 942                                    + line_layout.x_for_index(range.start.column() as usize)
 943                                    - scroll_left
 944                            } else {
 945                                content_origin.x() - scroll_left
 946                            },
 947                            end_x: if row == range.end.row() {
 948                                content_origin.x()
 949                                    + line_layout.x_for_index(range.end.column() as usize)
 950                                    - scroll_left
 951                            } else {
 952                                content_origin.x() + line_layout.width() + line_end_overshoot
 953                                    - scroll_left
 954                            },
 955                        }
 956                    })
 957                    .collect(),
 958            };
 959
 960            highlighted_range.paint(bounds, cx.scene);
 961        }
 962    }
 963
 964    fn paint_blocks(
 965        &mut self,
 966        bounds: RectF,
 967        visible_bounds: RectF,
 968        layout: &mut LayoutState,
 969        cx: &mut PaintContext,
 970    ) {
 971        let scroll_position = layout.position_map.snapshot.scroll_position();
 972        let scroll_left = scroll_position.x() * layout.position_map.em_width;
 973        let scroll_top = scroll_position.y() * layout.position_map.line_height;
 974
 975        for block in &mut layout.blocks {
 976            let mut origin = bounds.origin()
 977                + vec2f(
 978                    0.,
 979                    block.row as f32 * layout.position_map.line_height - scroll_top,
 980                );
 981            if !matches!(block.style, BlockStyle::Sticky) {
 982                origin += vec2f(-scroll_left, 0.);
 983            }
 984            block.element.paint(origin, visible_bounds, cx);
 985        }
 986    }
 987
 988    fn max_line_number_width(&self, snapshot: &EditorSnapshot, cx: &LayoutContext) -> f32 {
 989        let digit_count = (snapshot.max_buffer_row() as f32).log10().floor() as usize + 1;
 990        let style = &self.style;
 991
 992        cx.text_layout_cache
 993            .layout_str(
 994                "1".repeat(digit_count).as_str(),
 995                style.text.font_size,
 996                &[(
 997                    digit_count,
 998                    RunStyle {
 999                        font_id: style.text.font_id,
1000                        color: Color::black(),
1001                        underline: Default::default(),
1002                    },
1003                )],
1004            )
1005            .width()
1006    }
1007
1008    //Folds contained in a hunk are ignored apart from shrinking visual size
1009    //If a fold contains any hunks then that fold line is marked as modified
1010    fn layout_git_gutters(
1011        &self,
1012        rows: Range<u32>,
1013        snapshot: &EditorSnapshot,
1014    ) -> Vec<DiffHunkLayout> {
1015        let start_row = DisplayPoint::new(rows.start, 0).to_point(snapshot).row;
1016        let end_row = DisplayPoint::new(rows.end, 0).to_point(snapshot).row;
1017
1018        let mut layouts = Vec::new();
1019        for hunk in snapshot
1020            .buffer_snapshot
1021            .git_diff_hunks_in_range(start_row..end_row)
1022        {
1023            let start = Point::new(hunk.buffer_range.start, 0);
1024            let hunk_content_end_row = hunk
1025                .buffer_range
1026                .end
1027                .saturating_sub(1)
1028                .max(hunk.buffer_range.start);
1029            let hunk_content_end = Point::new(
1030                hunk_content_end_row,
1031                snapshot.buffer_snapshot.line_len(hunk_content_end_row),
1032            );
1033            let end = Point::new(hunk.buffer_range.end, 0);
1034
1035            let is_folded = snapshot
1036                .folds_in_range(start..end)
1037                .any(|fold_range| {
1038                    let fold_point_range = fold_range.to_point(&snapshot.buffer_snapshot);
1039                    dbg!(&fold_point_range);
1040                    fold_point_range.contains(dbg!(&start))
1041                        && fold_point_range.contains(dbg!(&hunk_content_end))
1042                        || fold_point_range.end == hunk_content_end
1043                });
1044
1045            layouts.push(dbg!(DiffHunkLayout {
1046                visual_range: start.to_display_point(snapshot).row()
1047                    ..end.to_display_point(snapshot).row(),
1048                status: hunk.status(),
1049                is_folded,
1050            }));
1051        }
1052
1053        layouts
1054    }
1055
1056    fn layout_line_numbers(
1057        &self,
1058        rows: Range<u32>,
1059        active_rows: &BTreeMap<u32, bool>,
1060        snapshot: &EditorSnapshot,
1061        cx: &LayoutContext,
1062    ) -> Vec<Option<text_layout::Line>> {
1063        let style = &self.style;
1064        let include_line_numbers = snapshot.mode == EditorMode::Full;
1065        let mut line_number_layouts = Vec::with_capacity(rows.len());
1066        let mut line_number = String::new();
1067        for (ix, row) in snapshot
1068            .buffer_rows(rows.start)
1069            .take((rows.end - rows.start) as usize)
1070            .enumerate()
1071        {
1072            let display_row = rows.start + ix as u32;
1073            let color = if active_rows.contains_key(&display_row) {
1074                style.line_number_active
1075            } else {
1076                style.line_number
1077            };
1078            if let Some(buffer_row) = row {
1079                if include_line_numbers {
1080                    line_number.clear();
1081                    write!(&mut line_number, "{}", buffer_row + 1).unwrap();
1082                    line_number_layouts.push(Some(cx.text_layout_cache.layout_str(
1083                        &line_number,
1084                        style.text.font_size,
1085                        &[(
1086                            line_number.len(),
1087                            RunStyle {
1088                                font_id: style.text.font_id,
1089                                color,
1090                                underline: Default::default(),
1091                            },
1092                        )],
1093                    )));
1094                }
1095            } else {
1096                line_number_layouts.push(None);
1097            }
1098        }
1099
1100        line_number_layouts
1101    }
1102
1103    fn layout_lines(
1104        &mut self,
1105        rows: Range<u32>,
1106        snapshot: &EditorSnapshot,
1107        cx: &LayoutContext,
1108    ) -> Vec<text_layout::Line> {
1109        if rows.start >= rows.end {
1110            return Vec::new();
1111        }
1112
1113        // When the editor is empty and unfocused, then show the placeholder.
1114        if snapshot.is_empty() && !snapshot.is_focused() {
1115            let placeholder_style = self
1116                .style
1117                .placeholder_text
1118                .as_ref()
1119                .unwrap_or(&self.style.text);
1120            let placeholder_text = snapshot.placeholder_text();
1121            let placeholder_lines = placeholder_text
1122                .as_ref()
1123                .map_or("", AsRef::as_ref)
1124                .split('\n')
1125                .skip(rows.start as usize)
1126                .chain(iter::repeat(""))
1127                .take(rows.len());
1128            placeholder_lines
1129                .map(|line| {
1130                    cx.text_layout_cache.layout_str(
1131                        line,
1132                        placeholder_style.font_size,
1133                        &[(
1134                            line.len(),
1135                            RunStyle {
1136                                font_id: placeholder_style.font_id,
1137                                color: placeholder_style.color,
1138                                underline: Default::default(),
1139                            },
1140                        )],
1141                    )
1142                })
1143                .collect()
1144        } else {
1145            let style = &self.style;
1146            let chunks = snapshot.chunks(rows.clone(), true).map(|chunk| {
1147                let mut highlight_style = chunk
1148                    .syntax_highlight_id
1149                    .and_then(|id| id.style(&style.syntax));
1150
1151                if let Some(chunk_highlight) = chunk.highlight_style {
1152                    if let Some(highlight_style) = highlight_style.as_mut() {
1153                        highlight_style.highlight(chunk_highlight);
1154                    } else {
1155                        highlight_style = Some(chunk_highlight);
1156                    }
1157                }
1158
1159                let mut diagnostic_highlight = HighlightStyle::default();
1160
1161                if chunk.is_unnecessary {
1162                    diagnostic_highlight.fade_out = Some(style.unnecessary_code_fade);
1163                }
1164
1165                if let Some(severity) = chunk.diagnostic_severity {
1166                    // Omit underlines for HINT/INFO diagnostics on 'unnecessary' code.
1167                    if severity <= DiagnosticSeverity::WARNING || !chunk.is_unnecessary {
1168                        let diagnostic_style = super::diagnostic_style(severity, true, style);
1169                        diagnostic_highlight.underline = Some(Underline {
1170                            color: Some(diagnostic_style.message.text.color),
1171                            thickness: 1.0.into(),
1172                            squiggly: true,
1173                        });
1174                    }
1175                }
1176
1177                if let Some(highlight_style) = highlight_style.as_mut() {
1178                    highlight_style.highlight(diagnostic_highlight);
1179                } else {
1180                    highlight_style = Some(diagnostic_highlight);
1181                }
1182
1183                (chunk.text, highlight_style)
1184            });
1185            layout_highlighted_chunks(
1186                chunks,
1187                &style.text,
1188                cx.text_layout_cache,
1189                cx.font_cache,
1190                MAX_LINE_LEN,
1191                rows.len() as usize,
1192            )
1193        }
1194    }
1195
1196    #[allow(clippy::too_many_arguments)]
1197    fn layout_blocks(
1198        &mut self,
1199        rows: Range<u32>,
1200        snapshot: &EditorSnapshot,
1201        editor_width: f32,
1202        scroll_width: f32,
1203        gutter_padding: f32,
1204        gutter_width: f32,
1205        em_width: f32,
1206        text_x: f32,
1207        line_height: f32,
1208        style: &EditorStyle,
1209        line_layouts: &[text_layout::Line],
1210        cx: &mut LayoutContext,
1211    ) -> (f32, Vec<BlockLayout>) {
1212        let editor = if let Some(editor) = self.view.upgrade(cx) {
1213            editor
1214        } else {
1215            return Default::default();
1216        };
1217
1218        let tooltip_style = cx.global::<Settings>().theme.tooltip.clone();
1219        let scroll_x = snapshot.scroll_position.x();
1220        let (fixed_blocks, non_fixed_blocks) = snapshot
1221            .blocks_in_range(rows.clone())
1222            .partition::<Vec<_>, _>(|(_, block)| match block {
1223                TransformBlock::ExcerptHeader { .. } => false,
1224                TransformBlock::Custom(block) => block.style() == BlockStyle::Fixed,
1225            });
1226        let mut render_block = |block: &TransformBlock, width: f32| {
1227            let mut element = match block {
1228                TransformBlock::Custom(block) => {
1229                    let align_to = block
1230                        .position()
1231                        .to_point(&snapshot.buffer_snapshot)
1232                        .to_display_point(snapshot);
1233                    let anchor_x = text_x
1234                        + if rows.contains(&align_to.row()) {
1235                            line_layouts[(align_to.row() - rows.start) as usize]
1236                                .x_for_index(align_to.column() as usize)
1237                        } else {
1238                            layout_line(align_to.row(), snapshot, style, cx.text_layout_cache)
1239                                .x_for_index(align_to.column() as usize)
1240                        };
1241
1242                    cx.render(&editor, |_, cx| {
1243                        block.render(&mut BlockContext {
1244                            cx,
1245                            anchor_x,
1246                            gutter_padding,
1247                            line_height,
1248                            scroll_x,
1249                            gutter_width,
1250                            em_width,
1251                        })
1252                    })
1253                }
1254                TransformBlock::ExcerptHeader {
1255                    key,
1256                    buffer,
1257                    range,
1258                    starts_new_buffer,
1259                    ..
1260                } => {
1261                    let jump_icon = project::File::from_dyn(buffer.file()).map(|file| {
1262                        let jump_position = range
1263                            .primary
1264                            .as_ref()
1265                            .map_or(range.context.start, |primary| primary.start);
1266                        let jump_action = crate::Jump {
1267                            path: ProjectPath {
1268                                worktree_id: file.worktree_id(cx),
1269                                path: file.path.clone(),
1270                            },
1271                            position: language::ToPoint::to_point(&jump_position, buffer),
1272                            anchor: jump_position,
1273                        };
1274
1275                        enum JumpIcon {}
1276                        cx.render(&editor, |_, cx| {
1277                            MouseEventHandler::<JumpIcon>::new(*key, cx, |state, _| {
1278                                let style = style.jump_icon.style_for(state, false);
1279                                Svg::new("icons/arrow_up_right_8.svg")
1280                                    .with_color(style.color)
1281                                    .constrained()
1282                                    .with_width(style.icon_width)
1283                                    .aligned()
1284                                    .contained()
1285                                    .with_style(style.container)
1286                                    .constrained()
1287                                    .with_width(style.button_width)
1288                                    .with_height(style.button_width)
1289                                    .boxed()
1290                            })
1291                            .with_cursor_style(CursorStyle::PointingHand)
1292                            .on_click(MouseButton::Left, move |_, cx| {
1293                                cx.dispatch_action(jump_action.clone())
1294                            })
1295                            .with_tooltip::<JumpIcon, _>(
1296                                *key,
1297                                "Jump to Buffer".to_string(),
1298                                Some(Box::new(crate::OpenExcerpts)),
1299                                tooltip_style.clone(),
1300                                cx,
1301                            )
1302                            .aligned()
1303                            .flex_float()
1304                            .boxed()
1305                        })
1306                    });
1307
1308                    if *starts_new_buffer {
1309                        let style = &self.style.diagnostic_path_header;
1310                        let font_size =
1311                            (style.text_scale_factor * self.style.text.font_size).round();
1312
1313                        let mut filename = None;
1314                        let mut parent_path = None;
1315                        if let Some(file) = buffer.file() {
1316                            let path = file.path();
1317                            filename = path.file_name().map(|f| f.to_string_lossy().to_string());
1318                            parent_path =
1319                                path.parent().map(|p| p.to_string_lossy().to_string() + "/");
1320                        }
1321
1322                        Flex::row()
1323                            .with_child(
1324                                Label::new(
1325                                    filename.unwrap_or_else(|| "untitled".to_string()),
1326                                    style.filename.text.clone().with_font_size(font_size),
1327                                )
1328                                .contained()
1329                                .with_style(style.filename.container)
1330                                .aligned()
1331                                .boxed(),
1332                            )
1333                            .with_children(parent_path.map(|path| {
1334                                Label::new(path, style.path.text.clone().with_font_size(font_size))
1335                                    .contained()
1336                                    .with_style(style.path.container)
1337                                    .aligned()
1338                                    .boxed()
1339                            }))
1340                            .with_children(jump_icon)
1341                            .contained()
1342                            .with_style(style.container)
1343                            .with_padding_left(gutter_padding)
1344                            .with_padding_right(gutter_padding)
1345                            .expanded()
1346                            .named("path header block")
1347                    } else {
1348                        let text_style = self.style.text.clone();
1349                        Flex::row()
1350                            .with_child(Label::new("".to_string(), text_style).boxed())
1351                            .with_children(jump_icon)
1352                            .contained()
1353                            .with_padding_left(gutter_padding)
1354                            .with_padding_right(gutter_padding)
1355                            .expanded()
1356                            .named("collapsed context")
1357                    }
1358                }
1359            };
1360
1361            element.layout(
1362                SizeConstraint {
1363                    min: Vector2F::zero(),
1364                    max: vec2f(width, block.height() as f32 * line_height),
1365                },
1366                cx,
1367            );
1368            element
1369        };
1370
1371        let mut fixed_block_max_width = 0f32;
1372        let mut blocks = Vec::new();
1373        for (row, block) in fixed_blocks {
1374            let element = render_block(block, f32::INFINITY);
1375            fixed_block_max_width = fixed_block_max_width.max(element.size().x() + em_width);
1376            blocks.push(BlockLayout {
1377                row,
1378                element,
1379                style: BlockStyle::Fixed,
1380            });
1381        }
1382        for (row, block) in non_fixed_blocks {
1383            let style = match block {
1384                TransformBlock::Custom(block) => block.style(),
1385                TransformBlock::ExcerptHeader { .. } => BlockStyle::Sticky,
1386            };
1387            let width = match style {
1388                BlockStyle::Sticky => editor_width,
1389                BlockStyle::Flex => editor_width
1390                    .max(fixed_block_max_width)
1391                    .max(gutter_width + scroll_width),
1392                BlockStyle::Fixed => unreachable!(),
1393            };
1394            let element = render_block(block, width);
1395            blocks.push(BlockLayout {
1396                row,
1397                element,
1398                style,
1399            });
1400        }
1401        (
1402            scroll_width.max(fixed_block_max_width - gutter_width),
1403            blocks,
1404        )
1405    }
1406}
1407
1408/// Get the hunk that contains buffer_line, starting from start_idx
1409/// Returns none if there is none found, and
1410fn get_hunk(hunks: &[DiffHunk<u32>], buffer_line: u32) -> Option<&DiffHunk<u32>> {
1411    for i in 0..hunks.len() {
1412        // Safety: Index out of bounds is handled by the check above
1413        let hunk = hunks.get(i).unwrap();
1414        if hunk.buffer_range.contains(&(buffer_line as u32)) {
1415            return Some(hunk);
1416        } else if hunk.status() == DiffHunkStatus::Removed && buffer_line == hunk.buffer_range.start
1417        {
1418            return Some(hunk);
1419        } else if hunk.buffer_range.start > buffer_line as u32 {
1420            // If we've passed the buffer_line, just stop
1421            return None;
1422        }
1423    }
1424
1425    // We reached the end of the array without finding a hunk, just return none.
1426    return None;
1427}
1428
1429impl Element for EditorElement {
1430    type LayoutState = LayoutState;
1431    type PaintState = ();
1432
1433    fn layout(
1434        &mut self,
1435        constraint: SizeConstraint,
1436        cx: &mut LayoutContext,
1437    ) -> (Vector2F, Self::LayoutState) {
1438        let mut size = constraint.max;
1439        if size.x().is_infinite() {
1440            unimplemented!("we don't yet handle an infinite width constraint on buffer elements");
1441        }
1442
1443        let snapshot = self.snapshot(cx.app);
1444        let style = self.style.clone();
1445        let line_height = style.text.line_height(cx.font_cache);
1446
1447        let gutter_padding;
1448        let gutter_width;
1449        let gutter_margin;
1450        if snapshot.mode == EditorMode::Full {
1451            gutter_padding = style.text.em_width(cx.font_cache) * style.gutter_padding_factor;
1452            gutter_width = self.max_line_number_width(&snapshot, cx) + gutter_padding * 2.0;
1453            gutter_margin = -style.text.descent(cx.font_cache);
1454        } else {
1455            gutter_padding = 0.0;
1456            gutter_width = 0.0;
1457            gutter_margin = 0.0;
1458        };
1459
1460        let text_width = size.x() - gutter_width;
1461        let em_width = style.text.em_width(cx.font_cache);
1462        let em_advance = style.text.em_advance(cx.font_cache);
1463        let overscroll = vec2f(em_width, 0.);
1464        let snapshot = self.update_view(cx.app, |view, cx| {
1465            view.set_visible_line_count(size.y() / line_height);
1466
1467            let wrap_width = match view.soft_wrap_mode(cx) {
1468                SoftWrap::None => Some((MAX_LINE_LEN / 2) as f32 * em_advance),
1469                SoftWrap::EditorWidth => {
1470                    Some(text_width - gutter_margin - overscroll.x() - em_width)
1471                }
1472                SoftWrap::Column(column) => Some(column as f32 * em_advance),
1473            };
1474
1475            if view.set_wrap_width(wrap_width, cx) {
1476                view.snapshot(cx)
1477            } else {
1478                snapshot
1479            }
1480        });
1481
1482        let scroll_height = (snapshot.max_point().row() + 1) as f32 * line_height;
1483        if let EditorMode::AutoHeight { max_lines } = snapshot.mode {
1484            size.set_y(
1485                scroll_height
1486                    .min(constraint.max_along(Axis::Vertical))
1487                    .max(constraint.min_along(Axis::Vertical))
1488                    .min(line_height * max_lines as f32),
1489            )
1490        } else if let EditorMode::SingleLine = snapshot.mode {
1491            size.set_y(
1492                line_height
1493                    .min(constraint.max_along(Axis::Vertical))
1494                    .max(constraint.min_along(Axis::Vertical)),
1495            )
1496        } else if size.y().is_infinite() {
1497            size.set_y(scroll_height);
1498        }
1499        let gutter_size = vec2f(gutter_width, size.y());
1500        let text_size = vec2f(text_width, size.y());
1501
1502        let (autoscroll_horizontally, mut snapshot) = self.update_view(cx.app, |view, cx| {
1503            let autoscroll_horizontally = view.autoscroll_vertically(size.y(), line_height, cx);
1504            let snapshot = view.snapshot(cx);
1505            (autoscroll_horizontally, snapshot)
1506        });
1507
1508        let scroll_position = snapshot.scroll_position();
1509        // The scroll position is a fractional point, the whole number of which represents
1510        // the top of the window in terms of display rows.
1511        let start_row = scroll_position.y() as u32;
1512        let scroll_top = scroll_position.y() * line_height;
1513
1514        // Add 1 to ensure selections bleed off screen
1515        let end_row = 1 + cmp::min(
1516            ((scroll_top + size.y()) / line_height).ceil() as u32,
1517            snapshot.max_point().row(),
1518        );
1519
1520        let start_anchor = if start_row == 0 {
1521            Anchor::min()
1522        } else {
1523            snapshot
1524                .buffer_snapshot
1525                .anchor_before(DisplayPoint::new(start_row, 0).to_offset(&snapshot, Bias::Left))
1526        };
1527        let end_anchor = if end_row > snapshot.max_point().row() {
1528            Anchor::max()
1529        } else {
1530            snapshot
1531                .buffer_snapshot
1532                .anchor_before(DisplayPoint::new(end_row, 0).to_offset(&snapshot, Bias::Right))
1533        };
1534
1535        let mut selections: Vec<(ReplicaId, Vec<SelectionLayout>)> = Vec::new();
1536        let mut active_rows = BTreeMap::new();
1537        let mut highlighted_rows = None;
1538        let mut highlighted_ranges = Vec::new();
1539        self.update_view(cx.app, |view, cx| {
1540            let display_map = view.display_map.update(cx, |map, cx| map.snapshot(cx));
1541
1542            highlighted_rows = view.highlighted_rows();
1543            let theme = cx.global::<Settings>().theme.as_ref();
1544            highlighted_ranges = view.background_highlights_in_range(
1545                start_anchor.clone()..end_anchor.clone(),
1546                &display_map,
1547                theme,
1548            );
1549
1550            let mut remote_selections = HashMap::default();
1551            for (replica_id, line_mode, selection) in display_map
1552                .buffer_snapshot
1553                .remote_selections_in_range(&(start_anchor.clone()..end_anchor.clone()))
1554            {
1555                // The local selections match the leader's selections.
1556                if Some(replica_id) == view.leader_replica_id {
1557                    continue;
1558                }
1559                remote_selections
1560                    .entry(replica_id)
1561                    .or_insert(Vec::new())
1562                    .push(SelectionLayout::new(selection, line_mode, &display_map));
1563            }
1564            selections.extend(remote_selections);
1565
1566            if view.show_local_selections {
1567                let mut local_selections = view
1568                    .selections
1569                    .disjoint_in_range(start_anchor..end_anchor, cx);
1570                local_selections.extend(view.selections.pending(cx));
1571                for selection in &local_selections {
1572                    let is_empty = selection.start == selection.end;
1573                    let selection_start = snapshot.prev_line_boundary(selection.start).1;
1574                    let selection_end = snapshot.next_line_boundary(selection.end).1;
1575                    for row in cmp::max(selection_start.row(), start_row)
1576                        ..=cmp::min(selection_end.row(), end_row)
1577                    {
1578                        let contains_non_empty_selection =
1579                            active_rows.entry(row).or_insert(!is_empty);
1580                        *contains_non_empty_selection |= !is_empty;
1581                    }
1582                }
1583
1584                // Render the local selections in the leader's color when following.
1585                let local_replica_id = view
1586                    .leader_replica_id
1587                    .unwrap_or_else(|| view.replica_id(cx));
1588
1589                selections.push((
1590                    local_replica_id,
1591                    local_selections
1592                        .into_iter()
1593                        .map(|selection| {
1594                            SelectionLayout::new(selection, view.selections.line_mode, &display_map)
1595                        })
1596                        .collect(),
1597                ));
1598            }
1599        });
1600
1601        let line_number_layouts =
1602            self.layout_line_numbers(start_row..end_row, &active_rows, &snapshot, cx);
1603
1604        let hunk_layouts = self.layout_git_gutters(start_row..end_row, &snapshot);
1605
1606        let mut max_visible_line_width = 0.0;
1607        let line_layouts = self.layout_lines(start_row..end_row, &snapshot, cx);
1608        for line in &line_layouts {
1609            if line.width() > max_visible_line_width {
1610                max_visible_line_width = line.width();
1611            }
1612        }
1613
1614        let style = self.style.clone();
1615        let longest_line_width = layout_line(
1616            snapshot.longest_row(),
1617            &snapshot,
1618            &style,
1619            cx.text_layout_cache,
1620        )
1621        .width();
1622        let scroll_width = longest_line_width.max(max_visible_line_width) + overscroll.x();
1623        let em_width = style.text.em_width(cx.font_cache);
1624        let (scroll_width, blocks) = self.layout_blocks(
1625            start_row..end_row,
1626            &snapshot,
1627            size.x(),
1628            scroll_width,
1629            gutter_padding,
1630            gutter_width,
1631            em_width,
1632            gutter_width + gutter_margin,
1633            line_height,
1634            &style,
1635            &line_layouts,
1636            cx,
1637        );
1638
1639        let max_row = snapshot.max_point().row();
1640        let scroll_max = vec2f(
1641            ((scroll_width - text_size.x()) / em_width).max(0.0),
1642            max_row.saturating_sub(1) as f32,
1643        );
1644
1645        self.update_view(cx.app, |view, cx| {
1646            let clamped = view.clamp_scroll_left(scroll_max.x());
1647
1648            let autoscrolled = if autoscroll_horizontally {
1649                view.autoscroll_horizontally(
1650                    start_row,
1651                    text_size.x(),
1652                    scroll_width,
1653                    em_width,
1654                    &line_layouts,
1655                    cx,
1656                )
1657            } else {
1658                false
1659            };
1660
1661            if clamped || autoscrolled {
1662                snapshot = view.snapshot(cx);
1663            }
1664        });
1665
1666        let mut context_menu = None;
1667        let mut code_actions_indicator = None;
1668        let mut hover = None;
1669        cx.render(&self.view.upgrade(cx).unwrap(), |view, cx| {
1670            let newest_selection_head = view
1671                .selections
1672                .newest::<usize>(cx)
1673                .head()
1674                .to_display_point(&snapshot);
1675
1676            let style = view.style(cx);
1677            if (start_row..end_row).contains(&newest_selection_head.row()) {
1678                if view.context_menu_visible() {
1679                    context_menu =
1680                        view.render_context_menu(newest_selection_head, style.clone(), cx);
1681                }
1682
1683                code_actions_indicator = view
1684                    .render_code_actions_indicator(&style, cx)
1685                    .map(|indicator| (newest_selection_head.row(), indicator));
1686            }
1687
1688            let visible_rows = start_row..start_row + line_layouts.len() as u32;
1689            hover = view.hover_state.render(&snapshot, &style, visible_rows, cx);
1690        });
1691
1692        if let Some((_, context_menu)) = context_menu.as_mut() {
1693            context_menu.layout(
1694                SizeConstraint {
1695                    min: Vector2F::zero(),
1696                    max: vec2f(
1697                        cx.window_size.x() * 0.7,
1698                        (12. * line_height).min((size.y() - line_height) / 2.),
1699                    ),
1700                },
1701                cx,
1702            );
1703        }
1704
1705        if let Some((_, indicator)) = code_actions_indicator.as_mut() {
1706            indicator.layout(
1707                SizeConstraint::strict_along(
1708                    Axis::Vertical,
1709                    line_height * style.code_actions.vertical_scale,
1710                ),
1711                cx,
1712            );
1713        }
1714
1715        if let Some((_, hover_popovers)) = hover.as_mut() {
1716            for hover_popover in hover_popovers.iter_mut() {
1717                hover_popover.layout(
1718                    SizeConstraint {
1719                        min: Vector2F::zero(),
1720                        max: vec2f(
1721                            (120. * em_width) // Default size
1722                                .min(size.x() / 2.) // Shrink to half of the editor width
1723                                .max(MIN_POPOVER_CHARACTER_WIDTH * em_width), // Apply minimum width of 20 characters
1724                            (16. * line_height) // Default size
1725                                .min(size.y() / 2.) // Shrink to half of the editor height
1726                                .max(MIN_POPOVER_LINE_HEIGHT * line_height), // Apply minimum height of 4 lines
1727                        ),
1728                    },
1729                    cx,
1730                );
1731            }
1732        }
1733
1734        (
1735            size,
1736            LayoutState {
1737                position_map: Arc::new(PositionMap {
1738                    size,
1739                    scroll_max,
1740                    line_layouts,
1741                    line_height,
1742                    em_width,
1743                    em_advance,
1744                    snapshot,
1745                }),
1746                gutter_size,
1747                gutter_padding,
1748                text_size,
1749                gutter_margin,
1750                active_rows,
1751                highlighted_rows,
1752                highlighted_ranges,
1753                line_number_layouts,
1754                hunk_layouts,
1755                blocks,
1756                selections,
1757                context_menu,
1758                code_actions_indicator,
1759                hover_popovers: hover,
1760            },
1761        )
1762    }
1763
1764    fn paint(
1765        &mut self,
1766        bounds: RectF,
1767        visible_bounds: RectF,
1768        layout: &mut Self::LayoutState,
1769        cx: &mut PaintContext,
1770    ) -> Self::PaintState {
1771        cx.scene.push_layer(Some(bounds));
1772
1773        let gutter_bounds = RectF::new(bounds.origin(), layout.gutter_size);
1774        let text_bounds = RectF::new(
1775            bounds.origin() + vec2f(layout.gutter_size.x(), 0.0),
1776            layout.text_size,
1777        );
1778
1779        Self::attach_mouse_handlers(
1780            &self.view,
1781            &layout.position_map,
1782            visible_bounds,
1783            text_bounds,
1784            gutter_bounds,
1785            bounds,
1786            cx,
1787        );
1788
1789        self.paint_background(gutter_bounds, text_bounds, layout, cx);
1790        if layout.gutter_size.x() > 0. {
1791            self.paint_gutter(gutter_bounds, visible_bounds, layout, cx);
1792        }
1793        self.paint_text(text_bounds, visible_bounds, layout, cx);
1794
1795        if !layout.blocks.is_empty() {
1796            cx.scene.push_layer(Some(bounds));
1797            self.paint_blocks(bounds, visible_bounds, layout, cx);
1798            cx.scene.pop_layer();
1799        }
1800
1801        cx.scene.pop_layer();
1802    }
1803
1804    fn dispatch_event(
1805        &mut self,
1806        event: &Event,
1807        _: RectF,
1808        _: RectF,
1809        _: &mut LayoutState,
1810        _: &mut (),
1811        cx: &mut EventContext,
1812    ) -> bool {
1813        if let Event::ModifiersChanged(event) = event {
1814            self.modifiers_changed(*event, cx);
1815        }
1816
1817        false
1818    }
1819
1820    fn rect_for_text_range(
1821        &self,
1822        range_utf16: Range<usize>,
1823        bounds: RectF,
1824        _: RectF,
1825        layout: &Self::LayoutState,
1826        _: &Self::PaintState,
1827        _: &gpui::MeasurementContext,
1828    ) -> Option<RectF> {
1829        let text_bounds = RectF::new(
1830            bounds.origin() + vec2f(layout.gutter_size.x(), 0.0),
1831            layout.text_size,
1832        );
1833        let content_origin = text_bounds.origin() + vec2f(layout.gutter_margin, 0.);
1834        let scroll_position = layout.position_map.snapshot.scroll_position();
1835        let start_row = scroll_position.y() as u32;
1836        let scroll_top = scroll_position.y() * layout.position_map.line_height;
1837        let scroll_left = scroll_position.x() * layout.position_map.em_width;
1838
1839        let range_start = OffsetUtf16(range_utf16.start)
1840            .to_display_point(&layout.position_map.snapshot.display_snapshot);
1841        if range_start.row() < start_row {
1842            return None;
1843        }
1844
1845        let line = layout
1846            .position_map
1847            .line_layouts
1848            .get((range_start.row() - start_row) as usize)?;
1849        let range_start_x = line.x_for_index(range_start.column() as usize);
1850        let range_start_y = range_start.row() as f32 * layout.position_map.line_height;
1851        Some(RectF::new(
1852            content_origin
1853                + vec2f(
1854                    range_start_x,
1855                    range_start_y + layout.position_map.line_height,
1856                )
1857                - vec2f(scroll_left, scroll_top),
1858            vec2f(
1859                layout.position_map.em_width,
1860                layout.position_map.line_height,
1861            ),
1862        ))
1863    }
1864
1865    fn debug(
1866        &self,
1867        bounds: RectF,
1868        _: &Self::LayoutState,
1869        _: &Self::PaintState,
1870        _: &gpui::DebugContext,
1871    ) -> json::Value {
1872        json!({
1873            "type": "BufferElement",
1874            "bounds": bounds.to_json()
1875        })
1876    }
1877}
1878
1879pub struct LayoutState {
1880    position_map: Arc<PositionMap>,
1881    gutter_size: Vector2F,
1882    gutter_padding: f32,
1883    gutter_margin: f32,
1884    text_size: Vector2F,
1885    active_rows: BTreeMap<u32, bool>,
1886    highlighted_rows: Option<Range<u32>>,
1887    line_number_layouts: Vec<Option<text_layout::Line>>,
1888    hunk_layouts: Vec<DiffHunkLayout>,
1889    blocks: Vec<BlockLayout>,
1890    highlighted_ranges: Vec<(Range<DisplayPoint>, Color)>,
1891    selections: Vec<(ReplicaId, Vec<SelectionLayout>)>,
1892    context_menu: Option<(DisplayPoint, ElementBox)>,
1893    code_actions_indicator: Option<(u32, ElementBox)>,
1894    hover_popovers: Option<(DisplayPoint, Vec<ElementBox>)>,
1895}
1896
1897pub struct PositionMap {
1898    size: Vector2F,
1899    line_height: f32,
1900    scroll_max: Vector2F,
1901    em_width: f32,
1902    em_advance: f32,
1903    line_layouts: Vec<text_layout::Line>,
1904    snapshot: EditorSnapshot,
1905}
1906
1907impl PositionMap {
1908    /// Returns two display points:
1909    /// 1. The nearest *valid* position in the editor
1910    /// 2. An unclipped, potentially *invalid* position that maps directly to
1911    ///    the given pixel position.
1912    fn point_for_position(
1913        &self,
1914        text_bounds: RectF,
1915        position: Vector2F,
1916    ) -> (DisplayPoint, DisplayPoint) {
1917        let scroll_position = self.snapshot.scroll_position();
1918        let position = position - text_bounds.origin();
1919        let y = position.y().max(0.0).min(self.size.y());
1920        let x = position.x() + (scroll_position.x() * self.em_width);
1921        let row = (y / self.line_height + scroll_position.y()) as u32;
1922        let (column, x_overshoot) = if let Some(line) = self
1923            .line_layouts
1924            .get(row as usize - scroll_position.y() as usize)
1925        {
1926            if let Some(ix) = line.index_for_x(x) {
1927                (ix as u32, 0.0)
1928            } else {
1929                (line.len() as u32, 0f32.max(x - line.width()))
1930            }
1931        } else {
1932            (0, x)
1933        };
1934
1935        let mut target_point = DisplayPoint::new(row, column);
1936        let point = self.snapshot.clip_point(target_point, Bias::Left);
1937        *target_point.column_mut() += (x_overshoot / self.em_advance) as u32;
1938
1939        (point, target_point)
1940    }
1941}
1942
1943struct BlockLayout {
1944    row: u32,
1945    element: ElementBox,
1946    style: BlockStyle,
1947}
1948
1949fn layout_line(
1950    row: u32,
1951    snapshot: &EditorSnapshot,
1952    style: &EditorStyle,
1953    layout_cache: &TextLayoutCache,
1954) -> text_layout::Line {
1955    let mut line = snapshot.line(row);
1956
1957    if line.len() > MAX_LINE_LEN {
1958        let mut len = MAX_LINE_LEN;
1959        while !line.is_char_boundary(len) {
1960            len -= 1;
1961        }
1962
1963        line.truncate(len);
1964    }
1965
1966    layout_cache.layout_str(
1967        &line,
1968        style.text.font_size,
1969        &[(
1970            snapshot.line_len(row) as usize,
1971            RunStyle {
1972                font_id: style.text.font_id,
1973                color: Color::black(),
1974                underline: Default::default(),
1975            },
1976        )],
1977    )
1978}
1979
1980#[derive(Copy, Clone, PartialEq, Eq, Debug)]
1981pub enum CursorShape {
1982    Bar,
1983    Block,
1984    Underscore,
1985    Hollow,
1986}
1987
1988impl Default for CursorShape {
1989    fn default() -> Self {
1990        CursorShape::Bar
1991    }
1992}
1993
1994#[derive(Debug)]
1995pub struct Cursor {
1996    origin: Vector2F,
1997    block_width: f32,
1998    line_height: f32,
1999    color: Color,
2000    shape: CursorShape,
2001    block_text: Option<Line>,
2002}
2003
2004impl Cursor {
2005    pub fn new(
2006        origin: Vector2F,
2007        block_width: f32,
2008        line_height: f32,
2009        color: Color,
2010        shape: CursorShape,
2011        block_text: Option<Line>,
2012    ) -> Cursor {
2013        Cursor {
2014            origin,
2015            block_width,
2016            line_height,
2017            color,
2018            shape,
2019            block_text,
2020        }
2021    }
2022
2023    pub fn bounding_rect(&self, origin: Vector2F) -> RectF {
2024        RectF::new(
2025            self.origin + origin,
2026            vec2f(self.block_width, self.line_height),
2027        )
2028    }
2029
2030    pub fn paint(&self, origin: Vector2F, cx: &mut PaintContext) {
2031        let bounds = match self.shape {
2032            CursorShape::Bar => RectF::new(self.origin + origin, vec2f(2.0, self.line_height)),
2033            CursorShape::Block | CursorShape::Hollow => RectF::new(
2034                self.origin + origin,
2035                vec2f(self.block_width, self.line_height),
2036            ),
2037            CursorShape::Underscore => RectF::new(
2038                self.origin + origin + Vector2F::new(0.0, self.line_height - 2.0),
2039                vec2f(self.block_width, 2.0),
2040            ),
2041        };
2042
2043        //Draw background or border quad
2044        if matches!(self.shape, CursorShape::Hollow) {
2045            cx.scene.push_quad(Quad {
2046                bounds,
2047                background: None,
2048                border: Border::all(1., self.color),
2049                corner_radius: 0.,
2050            });
2051        } else {
2052            cx.scene.push_quad(Quad {
2053                bounds,
2054                background: Some(self.color),
2055                border: Default::default(),
2056                corner_radius: 0.,
2057            });
2058        }
2059
2060        if let Some(block_text) = &self.block_text {
2061            block_text.paint(self.origin + origin, bounds, self.line_height, cx);
2062        }
2063    }
2064
2065    pub fn shape(&self) -> CursorShape {
2066        self.shape
2067    }
2068}
2069
2070#[derive(Debug)]
2071pub struct HighlightedRange {
2072    pub start_y: f32,
2073    pub line_height: f32,
2074    pub lines: Vec<HighlightedRangeLine>,
2075    pub color: Color,
2076    pub corner_radius: f32,
2077}
2078
2079#[derive(Debug)]
2080pub struct HighlightedRangeLine {
2081    pub start_x: f32,
2082    pub end_x: f32,
2083}
2084
2085impl HighlightedRange {
2086    pub fn paint(&self, bounds: RectF, scene: &mut Scene) {
2087        if self.lines.len() >= 2 && self.lines[0].start_x > self.lines[1].end_x {
2088            self.paint_lines(self.start_y, &self.lines[0..1], bounds, scene);
2089            self.paint_lines(
2090                self.start_y + self.line_height,
2091                &self.lines[1..],
2092                bounds,
2093                scene,
2094            );
2095        } else {
2096            self.paint_lines(self.start_y, &self.lines, bounds, scene);
2097        }
2098    }
2099
2100    fn paint_lines(
2101        &self,
2102        start_y: f32,
2103        lines: &[HighlightedRangeLine],
2104        bounds: RectF,
2105        scene: &mut Scene,
2106    ) {
2107        if lines.is_empty() {
2108            return;
2109        }
2110
2111        let mut path = PathBuilder::new();
2112        let first_line = lines.first().unwrap();
2113        let last_line = lines.last().unwrap();
2114
2115        let first_top_left = vec2f(first_line.start_x, start_y);
2116        let first_top_right = vec2f(first_line.end_x, start_y);
2117
2118        let curve_height = vec2f(0., self.corner_radius);
2119        let curve_width = |start_x: f32, end_x: f32| {
2120            let max = (end_x - start_x) / 2.;
2121            let width = if max < self.corner_radius {
2122                max
2123            } else {
2124                self.corner_radius
2125            };
2126
2127            vec2f(width, 0.)
2128        };
2129
2130        let top_curve_width = curve_width(first_line.start_x, first_line.end_x);
2131        path.reset(first_top_right - top_curve_width);
2132        path.curve_to(first_top_right + curve_height, first_top_right);
2133
2134        let mut iter = lines.iter().enumerate().peekable();
2135        while let Some((ix, line)) = iter.next() {
2136            let bottom_right = vec2f(line.end_x, start_y + (ix + 1) as f32 * self.line_height);
2137
2138            if let Some((_, next_line)) = iter.peek() {
2139                let next_top_right = vec2f(next_line.end_x, bottom_right.y());
2140
2141                match next_top_right.x().partial_cmp(&bottom_right.x()).unwrap() {
2142                    Ordering::Equal => {
2143                        path.line_to(bottom_right);
2144                    }
2145                    Ordering::Less => {
2146                        let curve_width = curve_width(next_top_right.x(), bottom_right.x());
2147                        path.line_to(bottom_right - curve_height);
2148                        if self.corner_radius > 0. {
2149                            path.curve_to(bottom_right - curve_width, bottom_right);
2150                        }
2151                        path.line_to(next_top_right + curve_width);
2152                        if self.corner_radius > 0. {
2153                            path.curve_to(next_top_right + curve_height, next_top_right);
2154                        }
2155                    }
2156                    Ordering::Greater => {
2157                        let curve_width = curve_width(bottom_right.x(), next_top_right.x());
2158                        path.line_to(bottom_right - curve_height);
2159                        if self.corner_radius > 0. {
2160                            path.curve_to(bottom_right + curve_width, bottom_right);
2161                        }
2162                        path.line_to(next_top_right - curve_width);
2163                        if self.corner_radius > 0. {
2164                            path.curve_to(next_top_right + curve_height, next_top_right);
2165                        }
2166                    }
2167                }
2168            } else {
2169                let curve_width = curve_width(line.start_x, line.end_x);
2170                path.line_to(bottom_right - curve_height);
2171                if self.corner_radius > 0. {
2172                    path.curve_to(bottom_right - curve_width, bottom_right);
2173                }
2174
2175                let bottom_left = vec2f(line.start_x, bottom_right.y());
2176                path.line_to(bottom_left + curve_width);
2177                if self.corner_radius > 0. {
2178                    path.curve_to(bottom_left - curve_height, bottom_left);
2179                }
2180            }
2181        }
2182
2183        if first_line.start_x > last_line.start_x {
2184            let curve_width = curve_width(last_line.start_x, first_line.start_x);
2185            let second_top_left = vec2f(last_line.start_x, start_y + self.line_height);
2186            path.line_to(second_top_left + curve_height);
2187            if self.corner_radius > 0. {
2188                path.curve_to(second_top_left + curve_width, second_top_left);
2189            }
2190            let first_bottom_left = vec2f(first_line.start_x, second_top_left.y());
2191            path.line_to(first_bottom_left - curve_width);
2192            if self.corner_radius > 0. {
2193                path.curve_to(first_bottom_left - curve_height, first_bottom_left);
2194            }
2195        }
2196
2197        path.line_to(first_top_left + curve_height);
2198        if self.corner_radius > 0. {
2199            path.curve_to(first_top_left + top_curve_width, first_top_left);
2200        }
2201        path.line_to(first_top_right - top_curve_width);
2202
2203        scene.push_path(path.build(self.color, Some(bounds)));
2204    }
2205}
2206
2207pub fn scale_vertical_mouse_autoscroll_delta(delta: f32) -> f32 {
2208    delta.powf(1.5) / 100.0
2209}
2210
2211fn scale_horizontal_mouse_autoscroll_delta(delta: f32) -> f32 {
2212    delta.powf(1.2) / 300.0
2213}
2214
2215#[cfg(test)]
2216mod tests {
2217    use std::sync::Arc;
2218
2219    use super::*;
2220    use crate::{
2221        display_map::{BlockDisposition, BlockProperties},
2222        Editor, MultiBuffer,
2223    };
2224    use settings::Settings;
2225    use util::test::sample_text;
2226
2227    #[gpui::test]
2228    fn test_layout_line_numbers(cx: &mut gpui::MutableAppContext) {
2229        cx.set_global(Settings::test(cx));
2230        let buffer = MultiBuffer::build_simple(&sample_text(6, 6, 'a'), cx);
2231        let (window_id, editor) = cx.add_window(Default::default(), |cx| {
2232            Editor::new(EditorMode::Full, buffer, None, None, cx)
2233        });
2234        let element = EditorElement::new(
2235            editor.downgrade(),
2236            editor.read(cx).style(cx),
2237            CursorShape::Bar,
2238        );
2239
2240        let layouts = editor.update(cx, |editor, cx| {
2241            let snapshot = editor.snapshot(cx);
2242            let mut presenter = cx.build_presenter(window_id, 30., Default::default());
2243            let layout_cx = presenter.build_layout_context(Vector2F::zero(), false, cx);
2244            element.layout_line_numbers(0..6, &Default::default(), &snapshot, &layout_cx)
2245        });
2246        assert_eq!(layouts.len(), 6);
2247    }
2248
2249    #[gpui::test]
2250    fn test_layout_with_placeholder_text_and_blocks(cx: &mut gpui::MutableAppContext) {
2251        cx.set_global(Settings::test(cx));
2252        let buffer = MultiBuffer::build_simple("", cx);
2253        let (window_id, editor) = cx.add_window(Default::default(), |cx| {
2254            Editor::new(EditorMode::Full, buffer, None, None, cx)
2255        });
2256
2257        editor.update(cx, |editor, cx| {
2258            editor.set_placeholder_text("hello", cx);
2259            editor.insert_blocks(
2260                [BlockProperties {
2261                    style: BlockStyle::Fixed,
2262                    disposition: BlockDisposition::Above,
2263                    height: 3,
2264                    position: Anchor::min(),
2265                    render: Arc::new(|_| Empty::new().boxed()),
2266                }],
2267                cx,
2268            );
2269
2270            // Blur the editor so that it displays placeholder text.
2271            cx.blur();
2272        });
2273
2274        let mut element = EditorElement::new(
2275            editor.downgrade(),
2276            editor.read(cx).style(cx),
2277            CursorShape::Bar,
2278        );
2279
2280        let mut scene = Scene::new(1.0);
2281        let mut presenter = cx.build_presenter(window_id, 30., Default::default());
2282        let mut layout_cx = presenter.build_layout_context(Vector2F::zero(), false, cx);
2283        let (size, mut state) = element.layout(
2284            SizeConstraint::new(vec2f(500., 500.), vec2f(500., 500.)),
2285            &mut layout_cx,
2286        );
2287
2288        assert_eq!(state.position_map.line_layouts.len(), 4);
2289        assert_eq!(
2290            state
2291                .line_number_layouts
2292                .iter()
2293                .map(Option::is_some)
2294                .collect::<Vec<_>>(),
2295            &[false, false, false, true]
2296        );
2297
2298        // Don't panic.
2299        let bounds = RectF::new(Default::default(), size);
2300        let mut paint_cx = presenter.build_paint_context(&mut scene, bounds.size(), cx);
2301        element.paint(bounds, bounds, &mut state, &mut paint_cx);
2302    }
2303}