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,
  16};
  17use clock::ReplicaId;
  18use collections::{BTreeMap, HashMap};
  19use git::diff::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::{DerefMut, Range},
  47    sync::Arc,
  48};
  49
  50#[derive(Debug)]
  51struct DiffHunkLayout {
  52    visual_range: Range<u32>,
  53    status: DiffHunkStatus,
  54    is_folded: bool,
  55}
  56
  57struct SelectionLayout {
  58    head: DisplayPoint,
  59    range: Range<DisplayPoint>,
  60}
  61
  62impl SelectionLayout {
  63    fn new<T: ToPoint + ToDisplayPoint + Clone>(
  64        selection: Selection<T>,
  65        line_mode: bool,
  66        map: &DisplaySnapshot,
  67    ) -> Self {
  68        if line_mode {
  69            let selection = selection.map(|p| p.to_point(&map.buffer_snapshot));
  70            let point_range = map.expand_to_line(selection.range());
  71            Self {
  72                head: selection.head().to_display_point(map),
  73                range: point_range.start.to_display_point(map)
  74                    ..point_range.end.to_display_point(map),
  75            }
  76        } else {
  77            let selection = selection.map(|p| p.to_display_point(map));
  78            Self {
  79                head: selection.head(),
  80                range: selection.range(),
  81            }
  82        }
  83    }
  84}
  85
  86#[derive(Clone)]
  87pub struct EditorElement {
  88    view: WeakViewHandle<Editor>,
  89    style: Arc<EditorStyle>,
  90    cursor_shape: CursorShape,
  91}
  92
  93impl EditorElement {
  94    pub fn new(
  95        view: WeakViewHandle<Editor>,
  96        style: EditorStyle,
  97        cursor_shape: CursorShape,
  98    ) -> Self {
  99        Self {
 100            view,
 101            style: Arc::new(style),
 102            cursor_shape,
 103        }
 104    }
 105
 106    fn view<'a>(&self, cx: &'a AppContext) -> &'a Editor {
 107        self.view.upgrade(cx).unwrap().read(cx)
 108    }
 109
 110    fn update_view<F, T>(&self, cx: &mut MutableAppContext, f: F) -> T
 111    where
 112        F: FnOnce(&mut Editor, &mut ViewContext<Editor>) -> T,
 113    {
 114        self.view.upgrade(cx).unwrap().update(cx, f)
 115    }
 116
 117    fn snapshot(&self, cx: &mut MutableAppContext) -> EditorSnapshot {
 118        self.update_view(cx, |view, cx| view.snapshot(cx))
 119    }
 120
 121    fn attach_mouse_handlers(
 122        view: &WeakViewHandle<Editor>,
 123        position_map: &Arc<PositionMap>,
 124        visible_bounds: RectF,
 125        text_bounds: RectF,
 126        gutter_bounds: RectF,
 127        bounds: RectF,
 128        cx: &mut PaintContext,
 129    ) {
 130        enum EditorElementMouseHandlers {}
 131        cx.scene.push_mouse_region(
 132            MouseRegion::new::<EditorElementMouseHandlers>(view.id(), view.id(), visible_bounds)
 133                .on_down(MouseButton::Left, {
 134                    let position_map = position_map.clone();
 135                    move |e, cx| {
 136                        if !Self::mouse_down(
 137                            e.platform_event,
 138                            position_map.as_ref(),
 139                            text_bounds,
 140                            gutter_bounds,
 141                            cx,
 142                        ) {
 143                            cx.propogate_event();
 144                        }
 145                    }
 146                })
 147                .on_down(MouseButton::Right, {
 148                    let position_map = position_map.clone();
 149                    move |e, cx| {
 150                        if !Self::mouse_right_down(
 151                            e.position,
 152                            position_map.as_ref(),
 153                            text_bounds,
 154                            cx,
 155                        ) {
 156                            cx.propogate_event();
 157                        }
 158                    }
 159                })
 160                .on_up(MouseButton::Left, {
 161                    let view = view.clone();
 162                    let position_map = position_map.clone();
 163                    move |e, cx| {
 164                        if !Self::mouse_up(
 165                            view.clone(),
 166                            e.position,
 167                            e.cmd,
 168                            e.shift,
 169                            position_map.as_ref(),
 170                            text_bounds,
 171                            cx,
 172                        ) {
 173                            cx.propogate_event()
 174                        }
 175                    }
 176                })
 177                .on_drag(MouseButton::Left, {
 178                    let view = view.clone();
 179                    let position_map = position_map.clone();
 180                    move |e, cx| {
 181                        if !Self::mouse_dragged(
 182                            view.clone(),
 183                            e.platform_event,
 184                            position_map.as_ref(),
 185                            text_bounds,
 186                            cx,
 187                        ) {
 188                            cx.propogate_event()
 189                        }
 190                    }
 191                })
 192                .on_move({
 193                    let position_map = position_map.clone();
 194                    move |e, cx| {
 195                        if !Self::mouse_moved(e.platform_event, &position_map, text_bounds, cx) {
 196                            cx.propogate_event()
 197                        }
 198                    }
 199                })
 200                .on_scroll({
 201                    let position_map = position_map.clone();
 202                    move |e, cx| {
 203                        if !Self::scroll(e.position, e.delta, e.precise, &position_map, bounds, cx)
 204                        {
 205                            cx.propogate_event()
 206                        }
 207                    }
 208                }),
 209        );
 210    }
 211
 212    fn mouse_down(
 213        MouseButtonEvent {
 214            position,
 215            ctrl,
 216            alt,
 217            shift,
 218            cmd,
 219            mut click_count,
 220            ..
 221        }: MouseButtonEvent,
 222        position_map: &PositionMap,
 223        text_bounds: RectF,
 224        gutter_bounds: RectF,
 225        cx: &mut EventContext,
 226    ) -> bool {
 227        if gutter_bounds.contains_point(position) {
 228            click_count = 3; // Simulate triple-click when clicking the gutter to select lines
 229        } else if !text_bounds.contains_point(position) {
 230            return false;
 231        }
 232
 233        let (position, target_position) = position_map.point_for_position(text_bounds, position);
 234
 235        if shift && alt {
 236            cx.dispatch_action(Select(SelectPhase::BeginColumnar {
 237                position,
 238                goal_column: target_position.column(),
 239            }));
 240        } else if shift && !ctrl && !alt && !cmd {
 241            cx.dispatch_action(Select(SelectPhase::Extend {
 242                position,
 243                click_count,
 244            }));
 245        } else {
 246            cx.dispatch_action(Select(SelectPhase::Begin {
 247                position,
 248                add: alt,
 249                click_count,
 250            }));
 251        }
 252
 253        true
 254    }
 255
 256    fn mouse_right_down(
 257        position: Vector2F,
 258        position_map: &PositionMap,
 259        text_bounds: RectF,
 260        cx: &mut EventContext,
 261    ) -> bool {
 262        if !text_bounds.contains_point(position) {
 263            return false;
 264        }
 265
 266        let (point, _) = position_map.point_for_position(text_bounds, position);
 267
 268        cx.dispatch_action(DeployMouseContextMenu { position, point });
 269        true
 270    }
 271
 272    fn mouse_up(
 273        view: WeakViewHandle<Editor>,
 274        position: Vector2F,
 275        cmd: bool,
 276        shift: bool,
 277        position_map: &PositionMap,
 278        text_bounds: RectF,
 279        cx: &mut EventContext,
 280    ) -> bool {
 281        let view = view.upgrade(cx.app).unwrap().read(cx.app);
 282        let end_selection = view.has_pending_selection();
 283        let pending_nonempty_selections = view.has_pending_nonempty_selection();
 284
 285        if end_selection {
 286            cx.dispatch_action(Select(SelectPhase::End));
 287        }
 288
 289        if !pending_nonempty_selections && cmd && text_bounds.contains_point(position) {
 290            let (point, target_point) = position_map.point_for_position(text_bounds, position);
 291
 292            if point == target_point {
 293                if shift {
 294                    cx.dispatch_action(GoToFetchedTypeDefinition { point });
 295                } else {
 296                    cx.dispatch_action(GoToFetchedDefinition { point });
 297                }
 298
 299                return true;
 300            }
 301        }
 302
 303        end_selection
 304    }
 305
 306    fn mouse_dragged(
 307        view: WeakViewHandle<Editor>,
 308        MouseMovedEvent {
 309            cmd,
 310            shift,
 311            position,
 312            ..
 313        }: MouseMovedEvent,
 314        position_map: &PositionMap,
 315        text_bounds: RectF,
 316        cx: &mut EventContext,
 317    ) -> bool {
 318        // This will be handled more correctly once https://github.com/zed-industries/zed/issues/1218 is completed
 319        // Don't trigger hover popover if mouse is hovering over context menu
 320        let point = if text_bounds.contains_point(position) {
 321            let (point, target_point) = position_map.point_for_position(text_bounds, position);
 322            if point == target_point {
 323                Some(point)
 324            } else {
 325                None
 326            }
 327        } else {
 328            None
 329        };
 330
 331        cx.dispatch_action(UpdateGoToDefinitionLink {
 332            point,
 333            cmd_held: cmd,
 334            shift_held: shift,
 335        });
 336
 337        let view = view.upgrade(cx.app).unwrap().read(cx.app);
 338        if view.has_pending_selection() {
 339            let mut scroll_delta = Vector2F::zero();
 340
 341            let vertical_margin = position_map.line_height.min(text_bounds.height() / 3.0);
 342            let top = text_bounds.origin_y() + vertical_margin;
 343            let bottom = text_bounds.lower_left().y() - vertical_margin;
 344            if position.y() < top {
 345                scroll_delta.set_y(-scale_vertical_mouse_autoscroll_delta(top - position.y()))
 346            }
 347            if position.y() > bottom {
 348                scroll_delta.set_y(scale_vertical_mouse_autoscroll_delta(position.y() - bottom))
 349            }
 350
 351            let horizontal_margin = position_map.line_height.min(text_bounds.width() / 3.0);
 352            let left = text_bounds.origin_x() + horizontal_margin;
 353            let right = text_bounds.upper_right().x() - horizontal_margin;
 354            if position.x() < left {
 355                scroll_delta.set_x(-scale_horizontal_mouse_autoscroll_delta(
 356                    left - position.x(),
 357                ))
 358            }
 359            if position.x() > right {
 360                scroll_delta.set_x(scale_horizontal_mouse_autoscroll_delta(
 361                    position.x() - right,
 362                ))
 363            }
 364
 365            let (position, target_position) =
 366                position_map.point_for_position(text_bounds, position);
 367
 368            cx.dispatch_action(Select(SelectPhase::Update {
 369                position,
 370                goal_column: target_position.column(),
 371                scroll_position: (position_map.snapshot.scroll_position() + scroll_delta)
 372                    .clamp(Vector2F::zero(), position_map.scroll_max),
 373            }));
 374
 375            cx.dispatch_action(HoverAt { point });
 376            true
 377        } else {
 378            cx.dispatch_action(HoverAt { point });
 379            false
 380        }
 381    }
 382
 383    fn mouse_moved(
 384        MouseMovedEvent {
 385            cmd,
 386            shift,
 387            position,
 388            ..
 389        }: MouseMovedEvent,
 390        position_map: &PositionMap,
 391        text_bounds: RectF,
 392        cx: &mut EventContext,
 393    ) -> bool {
 394        // This will be handled more correctly once https://github.com/zed-industries/zed/issues/1218 is completed
 395        // Don't trigger hover popover if mouse is hovering over context menu
 396        let point = if text_bounds.contains_point(position) {
 397            let (point, target_point) = position_map.point_for_position(text_bounds, position);
 398            if point == target_point {
 399                Some(point)
 400            } else {
 401                None
 402            }
 403        } else {
 404            None
 405        };
 406
 407        cx.dispatch_action(UpdateGoToDefinitionLink {
 408            point,
 409            cmd_held: cmd,
 410            shift_held: shift,
 411        });
 412
 413        cx.dispatch_action(HoverAt { point });
 414        true
 415    }
 416
 417    fn modifiers_changed(&self, event: ModifiersChangedEvent, cx: &mut EventContext) -> bool {
 418        cx.dispatch_action(CmdShiftChanged {
 419            cmd_down: event.cmd,
 420            shift_down: event.shift,
 421        });
 422        false
 423    }
 424
 425    fn scroll(
 426        position: Vector2F,
 427        mut delta: Vector2F,
 428        precise: bool,
 429        position_map: &PositionMap,
 430        bounds: RectF,
 431        cx: &mut EventContext,
 432    ) -> bool {
 433        if !bounds.contains_point(position) {
 434            return false;
 435        }
 436
 437        let max_glyph_width = position_map.em_width;
 438        if !precise {
 439            delta *= vec2f(max_glyph_width, position_map.line_height);
 440        }
 441
 442        let scroll_position = position_map.snapshot.scroll_position();
 443        let x = (scroll_position.x() * max_glyph_width - delta.x()) / max_glyph_width;
 444        let y =
 445            (scroll_position.y() * position_map.line_height - delta.y()) / position_map.line_height;
 446        let scroll_position = vec2f(x, y).clamp(Vector2F::zero(), position_map.scroll_max);
 447
 448        cx.dispatch_action(Scroll(scroll_position));
 449
 450        true
 451    }
 452
 453    fn paint_background(
 454        &self,
 455        gutter_bounds: RectF,
 456        text_bounds: RectF,
 457        layout: &LayoutState,
 458        cx: &mut PaintContext,
 459    ) {
 460        let bounds = gutter_bounds.union_rect(text_bounds);
 461        let scroll_top =
 462            layout.position_map.snapshot.scroll_position().y() * layout.position_map.line_height;
 463        cx.scene.push_quad(Quad {
 464            bounds: gutter_bounds,
 465            background: Some(self.style.gutter_background),
 466            border: Border::new(0., Color::transparent_black()),
 467            corner_radius: 0.,
 468        });
 469        cx.scene.push_quad(Quad {
 470            bounds: text_bounds,
 471            background: Some(self.style.background),
 472            border: Border::new(0., Color::transparent_black()),
 473            corner_radius: 0.,
 474        });
 475
 476        if let EditorMode::Full = layout.mode {
 477            let mut active_rows = layout.active_rows.iter().peekable();
 478            while let Some((start_row, contains_non_empty_selection)) = active_rows.next() {
 479                let mut end_row = *start_row;
 480                while active_rows.peek().map_or(false, |r| {
 481                    *r.0 == end_row + 1 && r.1 == contains_non_empty_selection
 482                }) {
 483                    active_rows.next().unwrap();
 484                    end_row += 1;
 485                }
 486
 487                if !contains_non_empty_selection {
 488                    let origin = vec2f(
 489                        bounds.origin_x(),
 490                        bounds.origin_y() + (layout.position_map.line_height * *start_row as f32)
 491                            - scroll_top,
 492                    );
 493                    let size = vec2f(
 494                        bounds.width(),
 495                        layout.position_map.line_height * (end_row - start_row + 1) as f32,
 496                    );
 497                    cx.scene.push_quad(Quad {
 498                        bounds: RectF::new(origin, size),
 499                        background: Some(self.style.active_line_background),
 500                        border: Border::default(),
 501                        corner_radius: 0.,
 502                    });
 503                }
 504            }
 505
 506            if let Some(highlighted_rows) = &layout.highlighted_rows {
 507                let origin = vec2f(
 508                    bounds.origin_x(),
 509                    bounds.origin_y()
 510                        + (layout.position_map.line_height * highlighted_rows.start as f32)
 511                        - scroll_top,
 512                );
 513                let size = vec2f(
 514                    bounds.width(),
 515                    layout.position_map.line_height * highlighted_rows.len() as f32,
 516                );
 517                cx.scene.push_quad(Quad {
 518                    bounds: RectF::new(origin, size),
 519                    background: Some(self.style.highlighted_line_background),
 520                    border: Border::default(),
 521                    corner_radius: 0.,
 522                });
 523            }
 524        }
 525    }
 526
 527    fn paint_gutter(
 528        &mut self,
 529        bounds: RectF,
 530        visible_bounds: RectF,
 531        layout: &mut LayoutState,
 532        cx: &mut PaintContext,
 533    ) {
 534        let line_height = layout.position_map.line_height;
 535
 536        let scroll_position = layout.position_map.snapshot.scroll_position();
 537        let scroll_top = scroll_position.y() * line_height;
 538
 539        let show_gutter = matches!(
 540            &cx.global::<Settings>()
 541                .git_overrides
 542                .git_gutter
 543                .unwrap_or_default(),
 544            GitGutter::TrackedFiles
 545        );
 546
 547        if show_gutter {
 548            Self::paint_diff_hunks(bounds, layout, cx);
 549        }
 550
 551        for (ix, line) in layout.line_number_layouts.iter().enumerate() {
 552            if let Some(line) = line {
 553                let line_origin = bounds.origin()
 554                    + vec2f(
 555                        bounds.width() - line.width() - layout.gutter_padding,
 556                        ix as f32 * line_height - (scroll_top % line_height),
 557                    );
 558
 559                line.paint(line_origin, visible_bounds, line_height, cx);
 560            }
 561        }
 562
 563        if let Some((row, indicator)) = layout.code_actions_indicator.as_mut() {
 564            let mut x = bounds.width() - layout.gutter_padding;
 565            let mut y = *row as f32 * line_height - scroll_top;
 566            x += ((layout.gutter_padding + layout.gutter_margin) - indicator.size().x()) / 2.;
 567            y += (line_height - indicator.size().y()) / 2.;
 568            indicator.paint(bounds.origin() + vec2f(x, y), visible_bounds, cx);
 569        }
 570    }
 571
 572    fn paint_diff_hunks(bounds: RectF, layout: &mut LayoutState, cx: &mut PaintContext) {
 573        let diff_style = &cx.global::<Settings>().theme.editor.diff.clone();
 574        let line_height = layout.position_map.line_height;
 575
 576        let scroll_position = layout.position_map.snapshot.scroll_position();
 577        let scroll_top = scroll_position.y() * line_height;
 578
 579        for hunk in &layout.hunk_layouts {
 580            let color = match (hunk.status, hunk.is_folded) {
 581                (DiffHunkStatus::Added, false) => diff_style.inserted,
 582                (DiffHunkStatus::Modified, false) => diff_style.modified,
 583
 584                //TODO: This rendering is entirely a horrible hack
 585                (DiffHunkStatus::Removed, false) => {
 586                    let row = hunk.visual_range.start;
 587
 588                    let offset = line_height / 2.;
 589                    let start_y = row as f32 * line_height - offset - scroll_top;
 590                    let end_y = start_y + line_height;
 591
 592                    let width = diff_style.removed_width_em * line_height;
 593                    let highlight_origin = bounds.origin() + vec2f(-width, start_y);
 594                    let highlight_size = vec2f(width * 2., end_y - start_y);
 595                    let highlight_bounds = RectF::new(highlight_origin, highlight_size);
 596
 597                    cx.scene.push_quad(Quad {
 598                        bounds: highlight_bounds,
 599                        background: Some(diff_style.deleted),
 600                        border: Border::new(0., Color::transparent_black()),
 601                        corner_radius: 1. * line_height,
 602                    });
 603
 604                    continue;
 605                }
 606
 607                (_, true) => {
 608                    let row = hunk.visual_range.start;
 609                    let start_y = row as f32 * line_height - scroll_top;
 610                    let end_y = start_y + line_height;
 611
 612                    let width = diff_style.removed_width_em * line_height;
 613                    let highlight_origin = bounds.origin() + vec2f(-width, start_y);
 614                    let highlight_size = vec2f(width * 2., end_y - start_y);
 615                    let highlight_bounds = RectF::new(highlight_origin, highlight_size);
 616
 617                    cx.scene.push_quad(Quad {
 618                        bounds: highlight_bounds,
 619                        background: Some(diff_style.modified),
 620                        border: Border::new(0., Color::transparent_black()),
 621                        corner_radius: 1. * line_height,
 622                    });
 623
 624                    continue;
 625                }
 626            };
 627
 628            let start_row = hunk.visual_range.start;
 629            let end_row = hunk.visual_range.end;
 630
 631            let start_y = start_row as f32 * line_height - scroll_top;
 632            let end_y = end_row as f32 * line_height - scroll_top;
 633
 634            let width = diff_style.width_em * line_height;
 635            let highlight_origin = bounds.origin() + vec2f(-width, start_y);
 636            let highlight_size = vec2f(width * 2., end_y - start_y);
 637            let highlight_bounds = RectF::new(highlight_origin, highlight_size);
 638
 639            cx.scene.push_quad(Quad {
 640                bounds: highlight_bounds,
 641                background: Some(color),
 642                border: Border::new(0., Color::transparent_black()),
 643                corner_radius: diff_style.corner_radius * line_height,
 644            });
 645        }
 646    }
 647
 648    fn paint_text(
 649        &mut self,
 650        bounds: RectF,
 651        visible_bounds: RectF,
 652        layout: &mut LayoutState,
 653        cx: &mut PaintContext,
 654    ) {
 655        let view = self.view(cx.app);
 656        let style = &self.style;
 657        let local_replica_id = view.replica_id(cx);
 658        let scroll_position = layout.position_map.snapshot.scroll_position();
 659        let start_row = layout.visible_display_row_range.start;
 660        let scroll_top = scroll_position.y() * layout.position_map.line_height;
 661        let max_glyph_width = layout.position_map.em_width;
 662        let scroll_left = scroll_position.x() * max_glyph_width;
 663        let content_origin = bounds.origin() + vec2f(layout.gutter_margin, 0.);
 664
 665        cx.scene.push_layer(Some(bounds));
 666
 667        cx.scene.push_cursor_region(CursorRegion {
 668            bounds,
 669            style: if !view.link_go_to_definition_state.definitions.is_empty() {
 670                CursorStyle::PointingHand
 671            } else {
 672                CursorStyle::IBeam
 673            },
 674        });
 675
 676        for (range, color) in &layout.highlighted_ranges {
 677            self.paint_highlighted_range(
 678                range.clone(),
 679                *color,
 680                0.,
 681                0.15 * layout.position_map.line_height,
 682                layout,
 683                content_origin,
 684                scroll_top,
 685                scroll_left,
 686                bounds,
 687                cx,
 688            );
 689        }
 690
 691        let mut cursors = SmallVec::<[Cursor; 32]>::new();
 692        for (replica_id, selections) in &layout.selections {
 693            let selection_style = style.replica_selection_style(*replica_id);
 694            let corner_radius = 0.15 * layout.position_map.line_height;
 695
 696            for selection in selections {
 697                self.paint_highlighted_range(
 698                    selection.range.clone(),
 699                    selection_style.selection,
 700                    corner_radius,
 701                    corner_radius * 2.,
 702                    layout,
 703                    content_origin,
 704                    scroll_top,
 705                    scroll_left,
 706                    bounds,
 707                    cx,
 708                );
 709
 710                if view.show_local_cursors() || *replica_id != local_replica_id {
 711                    let cursor_position = selection.head;
 712                    if layout
 713                        .visible_display_row_range
 714                        .contains(&cursor_position.row())
 715                    {
 716                        let cursor_row_layout = &layout.position_map.line_layouts
 717                            [(cursor_position.row() - start_row) as usize];
 718                        let cursor_column = cursor_position.column() as usize;
 719
 720                        let cursor_character_x = cursor_row_layout.x_for_index(cursor_column);
 721                        let mut block_width =
 722                            cursor_row_layout.x_for_index(cursor_column + 1) - cursor_character_x;
 723                        if block_width == 0.0 {
 724                            block_width = layout.position_map.em_width;
 725                        }
 726                        let block_text = if let CursorShape::Block = self.cursor_shape {
 727                            layout
 728                                .position_map
 729                                .snapshot
 730                                .chars_at(cursor_position)
 731                                .next()
 732                                .and_then(|(character, _)| {
 733                                    let font_id =
 734                                        cursor_row_layout.font_for_index(cursor_column)?;
 735                                    let text = character.to_string();
 736
 737                                    Some(cx.text_layout_cache.layout_str(
 738                                        &text,
 739                                        cursor_row_layout.font_size(),
 740                                        &[(
 741                                            text.len(),
 742                                            RunStyle {
 743                                                font_id,
 744                                                color: style.background,
 745                                                underline: Default::default(),
 746                                            },
 747                                        )],
 748                                    ))
 749                                })
 750                        } else {
 751                            None
 752                        };
 753
 754                        let x = cursor_character_x - scroll_left;
 755                        let y = cursor_position.row() as f32 * layout.position_map.line_height
 756                            - scroll_top;
 757                        cursors.push(Cursor {
 758                            color: selection_style.cursor,
 759                            block_width,
 760                            origin: vec2f(x, y),
 761                            line_height: layout.position_map.line_height,
 762                            shape: self.cursor_shape,
 763                            block_text,
 764                        });
 765                    }
 766                }
 767            }
 768        }
 769
 770        if let Some(visible_text_bounds) = bounds.intersection(visible_bounds) {
 771            // Draw glyphs
 772            for (ix, line) in layout.position_map.line_layouts.iter().enumerate() {
 773                let row = start_row + ix as u32;
 774                line.paint(
 775                    content_origin
 776                        + vec2f(
 777                            -scroll_left,
 778                            row as f32 * layout.position_map.line_height - scroll_top,
 779                        ),
 780                    visible_text_bounds,
 781                    layout.position_map.line_height,
 782                    cx,
 783                );
 784            }
 785        }
 786
 787        cx.scene.push_layer(Some(bounds));
 788        for cursor in cursors {
 789            cursor.paint(content_origin, cx);
 790        }
 791        cx.scene.pop_layer();
 792
 793        if let Some((position, context_menu)) = layout.context_menu.as_mut() {
 794            cx.scene.push_stacking_context(None);
 795            let cursor_row_layout =
 796                &layout.position_map.line_layouts[(position.row() - start_row) as usize];
 797            let x = cursor_row_layout.x_for_index(position.column() as usize) - scroll_left;
 798            let y = (position.row() + 1) as f32 * layout.position_map.line_height - scroll_top;
 799            let mut list_origin = content_origin + vec2f(x, y);
 800            let list_width = context_menu.size().x();
 801            let list_height = context_menu.size().y();
 802
 803            // Snap the right edge of the list to the right edge of the window if
 804            // its horizontal bounds overflow.
 805            if list_origin.x() + list_width > cx.window_size.x() {
 806                list_origin.set_x((cx.window_size.x() - list_width).max(0.));
 807            }
 808
 809            if list_origin.y() + list_height > bounds.max_y() {
 810                list_origin.set_y(list_origin.y() - layout.position_map.line_height - list_height);
 811            }
 812
 813            context_menu.paint(
 814                list_origin,
 815                RectF::from_points(Vector2F::zero(), vec2f(f32::MAX, f32::MAX)), // Let content bleed outside of editor
 816                cx,
 817            );
 818
 819            cx.scene.pop_stacking_context();
 820        }
 821
 822        if let Some((position, hover_popovers)) = layout.hover_popovers.as_mut() {
 823            cx.scene.push_stacking_context(None);
 824
 825            // This is safe because we check on layout whether the required row is available
 826            let hovered_row_layout =
 827                &layout.position_map.line_layouts[(position.row() - start_row) as usize];
 828
 829            // Minimum required size: Take the first popover, and add 1.5 times the minimum popover
 830            // height. This is the size we will use to decide whether to render popovers above or below
 831            // the hovered line.
 832            let first_size = hover_popovers[0].size();
 833            let height_to_reserve = first_size.y()
 834                + 1.5 * MIN_POPOVER_LINE_HEIGHT as f32 * layout.position_map.line_height;
 835
 836            // Compute Hovered Point
 837            let x = hovered_row_layout.x_for_index(position.column() as usize) - scroll_left;
 838            let y = position.row() as f32 * layout.position_map.line_height - scroll_top;
 839            let hovered_point = content_origin + vec2f(x, y);
 840
 841            if hovered_point.y() - height_to_reserve > 0.0 {
 842                // There is enough space above. Render popovers above the hovered point
 843                let mut current_y = hovered_point.y();
 844                for hover_popover in hover_popovers {
 845                    let size = hover_popover.size();
 846                    let mut popover_origin = vec2f(hovered_point.x(), current_y - size.y());
 847
 848                    let x_out_of_bounds = bounds.max_x() - (popover_origin.x() + size.x());
 849                    if x_out_of_bounds < 0.0 {
 850                        popover_origin.set_x(popover_origin.x() + x_out_of_bounds);
 851                    }
 852
 853                    hover_popover.paint(
 854                        popover_origin,
 855                        RectF::from_points(Vector2F::zero(), vec2f(f32::MAX, f32::MAX)), // Let content bleed outside of editor
 856                        cx,
 857                    );
 858
 859                    current_y = popover_origin.y() - HOVER_POPOVER_GAP;
 860                }
 861            } else {
 862                // There is not enough space above. Render popovers below the hovered point
 863                let mut current_y = hovered_point.y() + layout.position_map.line_height;
 864                for hover_popover in hover_popovers {
 865                    let size = hover_popover.size();
 866                    let mut popover_origin = vec2f(hovered_point.x(), current_y);
 867
 868                    let x_out_of_bounds = bounds.max_x() - (popover_origin.x() + size.x());
 869                    if x_out_of_bounds < 0.0 {
 870                        popover_origin.set_x(popover_origin.x() + x_out_of_bounds);
 871                    }
 872
 873                    hover_popover.paint(
 874                        popover_origin,
 875                        RectF::from_points(Vector2F::zero(), vec2f(f32::MAX, f32::MAX)), // Let content bleed outside of editor
 876                        cx,
 877                    );
 878
 879                    current_y = popover_origin.y() + size.y() + HOVER_POPOVER_GAP;
 880                }
 881            }
 882
 883            cx.scene.pop_stacking_context();
 884        }
 885
 886        cx.scene.pop_layer();
 887    }
 888
 889    fn paint_scrollbar(&mut self, bounds: RectF, layout: &mut LayoutState, cx: &mut PaintContext) {
 890        enum ScrollbarMouseHandlers {}
 891        if layout.mode != EditorMode::Full {
 892            return;
 893        }
 894
 895        let view = self.view.clone();
 896        let style = &self.style.theme.scrollbar;
 897
 898        let top = bounds.min_y();
 899        let bottom = bounds.max_y();
 900        let right = bounds.max_x();
 901        let left = right - style.width;
 902        let row_range = &layout.scrollbar_row_range;
 903        let max_row = layout.max_row as f32 + (row_range.end - row_range.start);
 904
 905        let mut height = bounds.height();
 906        let mut first_row_y_offset = 0.0;
 907
 908        // Impose a minimum height on the scrollbar thumb
 909        let min_thumb_height =
 910            style.min_height_factor * cx.font_cache.line_height(self.style.text.font_size);
 911        let thumb_height = (row_range.end - row_range.start) * height / max_row;
 912        if thumb_height < min_thumb_height {
 913            first_row_y_offset = (min_thumb_height - thumb_height) / 2.0;
 914            height -= min_thumb_height - thumb_height;
 915        }
 916
 917        let y_for_row = |row: f32| -> f32 { top + first_row_y_offset + row * height / max_row };
 918
 919        let thumb_top = y_for_row(row_range.start) - first_row_y_offset;
 920        let thumb_bottom = y_for_row(row_range.end) + first_row_y_offset;
 921        let track_bounds = RectF::from_points(vec2f(left, top), vec2f(right, bottom));
 922        let thumb_bounds = RectF::from_points(vec2f(left, thumb_top), vec2f(right, thumb_bottom));
 923
 924        if layout.show_scrollbars {
 925            cx.scene.push_quad(Quad {
 926                bounds: track_bounds,
 927                border: style.track.border,
 928                background: style.track.background_color,
 929                ..Default::default()
 930            });
 931            cx.scene.push_quad(Quad {
 932                bounds: thumb_bounds,
 933                border: style.thumb.border,
 934                background: style.thumb.background_color,
 935                corner_radius: style.thumb.corner_radius,
 936            });
 937        }
 938
 939        cx.scene.push_cursor_region(CursorRegion {
 940            bounds: track_bounds,
 941            style: CursorStyle::Arrow,
 942        });
 943        cx.scene.push_mouse_region(
 944            MouseRegion::new::<ScrollbarMouseHandlers>(view.id(), view.id(), track_bounds)
 945                .on_move({
 946                    let view = view.clone();
 947                    move |_, cx| {
 948                        if let Some(view) = view.upgrade(cx.deref_mut()) {
 949                            view.update(cx.deref_mut(), |view, cx| {
 950                                view.make_scrollbar_visible(cx);
 951                            });
 952                        }
 953                    }
 954                })
 955                .on_down(MouseButton::Left, {
 956                    let view = view.clone();
 957                    let row_range = row_range.clone();
 958                    move |e, cx| {
 959                        let y = e.position.y();
 960                        if let Some(view) = view.upgrade(cx.deref_mut()) {
 961                            view.update(cx.deref_mut(), |view, cx| {
 962                                if y < thumb_top || thumb_bottom < y {
 963                                    let center_row =
 964                                        ((y - top) * max_row as f32 / height).round() as u32;
 965                                    let top_row = center_row.saturating_sub(
 966                                        (row_range.end - row_range.start) as u32 / 2,
 967                                    );
 968                                    let mut position = view.scroll_position(cx);
 969                                    position.set_y(top_row as f32);
 970                                    view.set_scroll_position(position, cx);
 971                                } else {
 972                                    view.make_scrollbar_visible(cx);
 973                                }
 974                            });
 975                        }
 976                    }
 977                })
 978                .on_drag(MouseButton::Left, {
 979                    let view = view.clone();
 980                    move |e, cx| {
 981                        let y = e.prev_mouse_position.y();
 982                        let new_y = e.position.y();
 983                        if thumb_top < y && y < thumb_bottom {
 984                            if let Some(view) = view.upgrade(cx.deref_mut()) {
 985                                view.update(cx.deref_mut(), |view, cx| {
 986                                    let mut position = view.scroll_position(cx);
 987                                    position.set_y(
 988                                        position.y() + (new_y - y) * (max_row as f32) / height,
 989                                    );
 990                                    if position.y() < 0.0 {
 991                                        position.set_y(0.);
 992                                    }
 993                                    view.set_scroll_position(position, cx);
 994                                });
 995                            }
 996                        }
 997                    }
 998                }),
 999        );
1000    }
1001
1002    #[allow(clippy::too_many_arguments)]
1003    fn paint_highlighted_range(
1004        &self,
1005        range: Range<DisplayPoint>,
1006        color: Color,
1007        corner_radius: f32,
1008        line_end_overshoot: f32,
1009        layout: &LayoutState,
1010        content_origin: Vector2F,
1011        scroll_top: f32,
1012        scroll_left: f32,
1013        bounds: RectF,
1014        cx: &mut PaintContext,
1015    ) {
1016        let start_row = layout.visible_display_row_range.start;
1017        let end_row = layout.visible_display_row_range.end;
1018        if range.start != range.end {
1019            let row_range = if range.end.column() == 0 {
1020                cmp::max(range.start.row(), start_row)..cmp::min(range.end.row(), end_row)
1021            } else {
1022                cmp::max(range.start.row(), start_row)..cmp::min(range.end.row() + 1, end_row)
1023            };
1024
1025            let highlighted_range = HighlightedRange {
1026                color,
1027                line_height: layout.position_map.line_height,
1028                corner_radius,
1029                start_y: content_origin.y()
1030                    + row_range.start as f32 * layout.position_map.line_height
1031                    - scroll_top,
1032                lines: row_range
1033                    .into_iter()
1034                    .map(|row| {
1035                        let line_layout =
1036                            &layout.position_map.line_layouts[(row - start_row) as usize];
1037                        HighlightedRangeLine {
1038                            start_x: if row == range.start.row() {
1039                                content_origin.x()
1040                                    + line_layout.x_for_index(range.start.column() as usize)
1041                                    - scroll_left
1042                            } else {
1043                                content_origin.x() - scroll_left
1044                            },
1045                            end_x: if row == range.end.row() {
1046                                content_origin.x()
1047                                    + line_layout.x_for_index(range.end.column() as usize)
1048                                    - scroll_left
1049                            } else {
1050                                content_origin.x() + line_layout.width() + line_end_overshoot
1051                                    - scroll_left
1052                            },
1053                        }
1054                    })
1055                    .collect(),
1056            };
1057
1058            highlighted_range.paint(bounds, cx.scene);
1059        }
1060    }
1061
1062    fn paint_blocks(
1063        &mut self,
1064        bounds: RectF,
1065        visible_bounds: RectF,
1066        layout: &mut LayoutState,
1067        cx: &mut PaintContext,
1068    ) {
1069        let scroll_position = layout.position_map.snapshot.scroll_position();
1070        let scroll_left = scroll_position.x() * layout.position_map.em_width;
1071        let scroll_top = scroll_position.y() * layout.position_map.line_height;
1072
1073        for block in &mut layout.blocks {
1074            let mut origin = bounds.origin()
1075                + vec2f(
1076                    0.,
1077                    block.row as f32 * layout.position_map.line_height - scroll_top,
1078                );
1079            if !matches!(block.style, BlockStyle::Sticky) {
1080                origin += vec2f(-scroll_left, 0.);
1081            }
1082            block.element.paint(origin, visible_bounds, cx);
1083        }
1084    }
1085
1086    fn max_line_number_width(&self, snapshot: &EditorSnapshot, cx: &LayoutContext) -> f32 {
1087        let digit_count = (snapshot.max_buffer_row() as f32).log10().floor() as usize + 1;
1088        let style = &self.style;
1089
1090        cx.text_layout_cache
1091            .layout_str(
1092                "1".repeat(digit_count).as_str(),
1093                style.text.font_size,
1094                &[(
1095                    digit_count,
1096                    RunStyle {
1097                        font_id: style.text.font_id,
1098                        color: Color::black(),
1099                        underline: Default::default(),
1100                    },
1101                )],
1102            )
1103            .width()
1104    }
1105
1106    //Folds contained in a hunk are ignored apart from shrinking visual size
1107    //If a fold contains any hunks then that fold line is marked as modified
1108    fn layout_git_gutters(
1109        &self,
1110        rows: Range<u32>,
1111        snapshot: &EditorSnapshot,
1112    ) -> Vec<DiffHunkLayout> {
1113        let buffer_snapshot = &snapshot.buffer_snapshot;
1114        let visual_start = DisplayPoint::new(rows.start, 0).to_point(snapshot).row;
1115        let visual_end = DisplayPoint::new(rows.end, 0).to_point(snapshot).row;
1116        let hunks = buffer_snapshot.git_diff_hunks_in_range(visual_start..visual_end);
1117
1118        let mut layouts = Vec::<DiffHunkLayout>::new();
1119
1120        for hunk in hunks {
1121            let hunk_start_point = Point::new(hunk.buffer_range.start, 0);
1122            let hunk_end_point = Point::new(hunk.buffer_range.end, 0);
1123            let hunk_start_point_sub = Point::new(hunk.buffer_range.start.saturating_sub(1), 0);
1124            let hunk_end_point_sub = Point::new(
1125                hunk.buffer_range
1126                    .end
1127                    .saturating_sub(1)
1128                    .max(hunk.buffer_range.start),
1129                0,
1130            );
1131
1132            let is_removal = hunk.status() == DiffHunkStatus::Removed;
1133
1134            let folds_start = Point::new(hunk.buffer_range.start.saturating_sub(1), 0);
1135            let folds_end = Point::new(hunk.buffer_range.end + 1, 0);
1136            let folds_range = folds_start..folds_end;
1137
1138            let containing_fold = snapshot.folds_in_range(folds_range).find(|fold_range| {
1139                let fold_point_range = fold_range.to_point(buffer_snapshot);
1140                let fold_point_range = fold_point_range.start..=fold_point_range.end;
1141
1142                let folded_start = fold_point_range.contains(&hunk_start_point);
1143                let folded_end = fold_point_range.contains(&hunk_end_point_sub);
1144                let folded_start_sub = fold_point_range.contains(&hunk_start_point_sub);
1145
1146                (folded_start && folded_end) || (is_removal && folded_start_sub)
1147            });
1148
1149            let visual_range = if let Some(fold) = containing_fold {
1150                let row = fold.start.to_display_point(snapshot).row();
1151                row..row
1152            } else {
1153                let start = hunk_start_point.to_display_point(snapshot).row();
1154                let end = hunk_end_point.to_display_point(snapshot).row();
1155                start..end
1156            };
1157
1158            let has_existing_layout = match layouts.last() {
1159                Some(e) => visual_range == e.visual_range && e.status == hunk.status(),
1160                None => false,
1161            };
1162
1163            if !has_existing_layout {
1164                layouts.push(DiffHunkLayout {
1165                    visual_range,
1166                    status: hunk.status(),
1167                    is_folded: containing_fold.is_some(),
1168                });
1169            }
1170        }
1171
1172        layouts
1173    }
1174
1175    fn layout_line_numbers(
1176        &self,
1177        rows: Range<u32>,
1178        active_rows: &BTreeMap<u32, bool>,
1179        snapshot: &EditorSnapshot,
1180        cx: &LayoutContext,
1181    ) -> Vec<Option<text_layout::Line>> {
1182        let style = &self.style;
1183        let include_line_numbers = snapshot.mode == EditorMode::Full;
1184        let mut line_number_layouts = Vec::with_capacity(rows.len());
1185        let mut line_number = String::new();
1186        for (ix, row) in snapshot
1187            .buffer_rows(rows.start)
1188            .take((rows.end - rows.start) as usize)
1189            .enumerate()
1190        {
1191            let display_row = rows.start + ix as u32;
1192            let color = if active_rows.contains_key(&display_row) {
1193                style.line_number_active
1194            } else {
1195                style.line_number
1196            };
1197            if let Some(buffer_row) = row {
1198                if include_line_numbers {
1199                    line_number.clear();
1200                    write!(&mut line_number, "{}", buffer_row + 1).unwrap();
1201                    line_number_layouts.push(Some(cx.text_layout_cache.layout_str(
1202                        &line_number,
1203                        style.text.font_size,
1204                        &[(
1205                            line_number.len(),
1206                            RunStyle {
1207                                font_id: style.text.font_id,
1208                                color,
1209                                underline: Default::default(),
1210                            },
1211                        )],
1212                    )));
1213                }
1214            } else {
1215                line_number_layouts.push(None);
1216            }
1217        }
1218
1219        line_number_layouts
1220    }
1221
1222    fn layout_lines(
1223        &mut self,
1224        rows: Range<u32>,
1225        snapshot: &EditorSnapshot,
1226        cx: &LayoutContext,
1227    ) -> Vec<text_layout::Line> {
1228        if rows.start >= rows.end {
1229            return Vec::new();
1230        }
1231
1232        // When the editor is empty and unfocused, then show the placeholder.
1233        if snapshot.is_empty() && !snapshot.is_focused() {
1234            let placeholder_style = self
1235                .style
1236                .placeholder_text
1237                .as_ref()
1238                .unwrap_or(&self.style.text);
1239            let placeholder_text = snapshot.placeholder_text();
1240            let placeholder_lines = placeholder_text
1241                .as_ref()
1242                .map_or("", AsRef::as_ref)
1243                .split('\n')
1244                .skip(rows.start as usize)
1245                .chain(iter::repeat(""))
1246                .take(rows.len());
1247            placeholder_lines
1248                .map(|line| {
1249                    cx.text_layout_cache.layout_str(
1250                        line,
1251                        placeholder_style.font_size,
1252                        &[(
1253                            line.len(),
1254                            RunStyle {
1255                                font_id: placeholder_style.font_id,
1256                                color: placeholder_style.color,
1257                                underline: Default::default(),
1258                            },
1259                        )],
1260                    )
1261                })
1262                .collect()
1263        } else {
1264            let style = &self.style;
1265            let chunks = snapshot.chunks(rows.clone(), true).map(|chunk| {
1266                let mut highlight_style = chunk
1267                    .syntax_highlight_id
1268                    .and_then(|id| id.style(&style.syntax));
1269
1270                if let Some(chunk_highlight) = chunk.highlight_style {
1271                    if let Some(highlight_style) = highlight_style.as_mut() {
1272                        highlight_style.highlight(chunk_highlight);
1273                    } else {
1274                        highlight_style = Some(chunk_highlight);
1275                    }
1276                }
1277
1278                let mut diagnostic_highlight = HighlightStyle::default();
1279
1280                if chunk.is_unnecessary {
1281                    diagnostic_highlight.fade_out = Some(style.unnecessary_code_fade);
1282                }
1283
1284                if let Some(severity) = chunk.diagnostic_severity {
1285                    // Omit underlines for HINT/INFO diagnostics on 'unnecessary' code.
1286                    if severity <= DiagnosticSeverity::WARNING || !chunk.is_unnecessary {
1287                        let diagnostic_style = super::diagnostic_style(severity, true, style);
1288                        diagnostic_highlight.underline = Some(Underline {
1289                            color: Some(diagnostic_style.message.text.color),
1290                            thickness: 1.0.into(),
1291                            squiggly: true,
1292                        });
1293                    }
1294                }
1295
1296                if let Some(highlight_style) = highlight_style.as_mut() {
1297                    highlight_style.highlight(diagnostic_highlight);
1298                } else {
1299                    highlight_style = Some(diagnostic_highlight);
1300                }
1301
1302                (chunk.text, highlight_style)
1303            });
1304            layout_highlighted_chunks(
1305                chunks,
1306                &style.text,
1307                cx.text_layout_cache,
1308                cx.font_cache,
1309                MAX_LINE_LEN,
1310                rows.len() as usize,
1311            )
1312        }
1313    }
1314
1315    #[allow(clippy::too_many_arguments)]
1316    fn layout_blocks(
1317        &mut self,
1318        rows: Range<u32>,
1319        snapshot: &EditorSnapshot,
1320        editor_width: f32,
1321        scroll_width: f32,
1322        gutter_padding: f32,
1323        gutter_width: f32,
1324        em_width: f32,
1325        text_x: f32,
1326        line_height: f32,
1327        style: &EditorStyle,
1328        line_layouts: &[text_layout::Line],
1329        cx: &mut LayoutContext,
1330    ) -> (f32, Vec<BlockLayout>) {
1331        let editor = if let Some(editor) = self.view.upgrade(cx) {
1332            editor
1333        } else {
1334            return Default::default();
1335        };
1336
1337        let tooltip_style = cx.global::<Settings>().theme.tooltip.clone();
1338        let scroll_x = snapshot.scroll_position.x();
1339        let (fixed_blocks, non_fixed_blocks) = snapshot
1340            .blocks_in_range(rows.clone())
1341            .partition::<Vec<_>, _>(|(_, block)| match block {
1342                TransformBlock::ExcerptHeader { .. } => false,
1343                TransformBlock::Custom(block) => block.style() == BlockStyle::Fixed,
1344            });
1345        let mut render_block = |block: &TransformBlock, width: f32| {
1346            let mut element = match block {
1347                TransformBlock::Custom(block) => {
1348                    let align_to = block
1349                        .position()
1350                        .to_point(&snapshot.buffer_snapshot)
1351                        .to_display_point(snapshot);
1352                    let anchor_x = text_x
1353                        + if rows.contains(&align_to.row()) {
1354                            line_layouts[(align_to.row() - rows.start) as usize]
1355                                .x_for_index(align_to.column() as usize)
1356                        } else {
1357                            layout_line(align_to.row(), snapshot, style, cx.text_layout_cache)
1358                                .x_for_index(align_to.column() as usize)
1359                        };
1360
1361                    cx.render(&editor, |_, cx| {
1362                        block.render(&mut BlockContext {
1363                            cx,
1364                            anchor_x,
1365                            gutter_padding,
1366                            line_height,
1367                            scroll_x,
1368                            gutter_width,
1369                            em_width,
1370                        })
1371                    })
1372                }
1373                TransformBlock::ExcerptHeader {
1374                    key,
1375                    buffer,
1376                    range,
1377                    starts_new_buffer,
1378                    ..
1379                } => {
1380                    let jump_icon = project::File::from_dyn(buffer.file()).map(|file| {
1381                        let jump_position = range
1382                            .primary
1383                            .as_ref()
1384                            .map_or(range.context.start, |primary| primary.start);
1385                        let jump_action = crate::Jump {
1386                            path: ProjectPath {
1387                                worktree_id: file.worktree_id(cx),
1388                                path: file.path.clone(),
1389                            },
1390                            position: language::ToPoint::to_point(&jump_position, buffer),
1391                            anchor: jump_position,
1392                        };
1393
1394                        enum JumpIcon {}
1395                        cx.render(&editor, |_, cx| {
1396                            MouseEventHandler::<JumpIcon>::new(*key, cx, |state, _| {
1397                                let style = style.jump_icon.style_for(state, false);
1398                                Svg::new("icons/arrow_up_right_8.svg")
1399                                    .with_color(style.color)
1400                                    .constrained()
1401                                    .with_width(style.icon_width)
1402                                    .aligned()
1403                                    .contained()
1404                                    .with_style(style.container)
1405                                    .constrained()
1406                                    .with_width(style.button_width)
1407                                    .with_height(style.button_width)
1408                                    .boxed()
1409                            })
1410                            .with_cursor_style(CursorStyle::PointingHand)
1411                            .on_click(MouseButton::Left, move |_, cx| {
1412                                cx.dispatch_action(jump_action.clone())
1413                            })
1414                            .with_tooltip::<JumpIcon, _>(
1415                                *key,
1416                                "Jump to Buffer".to_string(),
1417                                Some(Box::new(crate::OpenExcerpts)),
1418                                tooltip_style.clone(),
1419                                cx,
1420                            )
1421                            .aligned()
1422                            .flex_float()
1423                            .boxed()
1424                        })
1425                    });
1426
1427                    if *starts_new_buffer {
1428                        let style = &self.style.diagnostic_path_header;
1429                        let font_size =
1430                            (style.text_scale_factor * self.style.text.font_size).round();
1431
1432                        let mut filename = None;
1433                        let mut parent_path = None;
1434                        if let Some(file) = buffer.file() {
1435                            let path = file.path();
1436                            filename = path.file_name().map(|f| f.to_string_lossy().to_string());
1437                            parent_path =
1438                                path.parent().map(|p| p.to_string_lossy().to_string() + "/");
1439                        }
1440
1441                        Flex::row()
1442                            .with_child(
1443                                Label::new(
1444                                    filename.unwrap_or_else(|| "untitled".to_string()),
1445                                    style.filename.text.clone().with_font_size(font_size),
1446                                )
1447                                .contained()
1448                                .with_style(style.filename.container)
1449                                .aligned()
1450                                .boxed(),
1451                            )
1452                            .with_children(parent_path.map(|path| {
1453                                Label::new(path, style.path.text.clone().with_font_size(font_size))
1454                                    .contained()
1455                                    .with_style(style.path.container)
1456                                    .aligned()
1457                                    .boxed()
1458                            }))
1459                            .with_children(jump_icon)
1460                            .contained()
1461                            .with_style(style.container)
1462                            .with_padding_left(gutter_padding)
1463                            .with_padding_right(gutter_padding)
1464                            .expanded()
1465                            .named("path header block")
1466                    } else {
1467                        let text_style = self.style.text.clone();
1468                        Flex::row()
1469                            .with_child(Label::new("".to_string(), text_style).boxed())
1470                            .with_children(jump_icon)
1471                            .contained()
1472                            .with_padding_left(gutter_padding)
1473                            .with_padding_right(gutter_padding)
1474                            .expanded()
1475                            .named("collapsed context")
1476                    }
1477                }
1478            };
1479
1480            element.layout(
1481                SizeConstraint {
1482                    min: Vector2F::zero(),
1483                    max: vec2f(width, block.height() as f32 * line_height),
1484                },
1485                cx,
1486            );
1487            element
1488        };
1489
1490        let mut fixed_block_max_width = 0f32;
1491        let mut blocks = Vec::new();
1492        for (row, block) in fixed_blocks {
1493            let element = render_block(block, f32::INFINITY);
1494            fixed_block_max_width = fixed_block_max_width.max(element.size().x() + em_width);
1495            blocks.push(BlockLayout {
1496                row,
1497                element,
1498                style: BlockStyle::Fixed,
1499            });
1500        }
1501        for (row, block) in non_fixed_blocks {
1502            let style = match block {
1503                TransformBlock::Custom(block) => block.style(),
1504                TransformBlock::ExcerptHeader { .. } => BlockStyle::Sticky,
1505            };
1506            let width = match style {
1507                BlockStyle::Sticky => editor_width,
1508                BlockStyle::Flex => editor_width
1509                    .max(fixed_block_max_width)
1510                    .max(gutter_width + scroll_width),
1511                BlockStyle::Fixed => unreachable!(),
1512            };
1513            let element = render_block(block, width);
1514            blocks.push(BlockLayout {
1515                row,
1516                element,
1517                style,
1518            });
1519        }
1520        (
1521            scroll_width.max(fixed_block_max_width - gutter_width),
1522            blocks,
1523        )
1524    }
1525}
1526
1527impl Element for EditorElement {
1528    type LayoutState = LayoutState;
1529    type PaintState = ();
1530
1531    fn layout(
1532        &mut self,
1533        constraint: SizeConstraint,
1534        cx: &mut LayoutContext,
1535    ) -> (Vector2F, Self::LayoutState) {
1536        let mut size = constraint.max;
1537        if size.x().is_infinite() {
1538            unimplemented!("we don't yet handle an infinite width constraint on buffer elements");
1539        }
1540
1541        let snapshot = self.snapshot(cx.app);
1542        let style = self.style.clone();
1543        let line_height = style.text.line_height(cx.font_cache);
1544
1545        let gutter_padding;
1546        let gutter_width;
1547        let gutter_margin;
1548        if snapshot.mode == EditorMode::Full {
1549            gutter_padding = style.text.em_width(cx.font_cache) * style.gutter_padding_factor;
1550            gutter_width = self.max_line_number_width(&snapshot, cx) + gutter_padding * 2.0;
1551            gutter_margin = -style.text.descent(cx.font_cache);
1552        } else {
1553            gutter_padding = 0.0;
1554            gutter_width = 0.0;
1555            gutter_margin = 0.0;
1556        };
1557
1558        let text_width = size.x() - gutter_width;
1559        let em_width = style.text.em_width(cx.font_cache);
1560        let em_advance = style.text.em_advance(cx.font_cache);
1561        let overscroll = vec2f(em_width, 0.);
1562        let snapshot = self.update_view(cx.app, |view, cx| {
1563            view.set_visible_line_count(size.y() / line_height);
1564
1565            let wrap_width = match view.soft_wrap_mode(cx) {
1566                SoftWrap::None => Some((MAX_LINE_LEN / 2) as f32 * em_advance),
1567                SoftWrap::EditorWidth => {
1568                    Some(text_width - gutter_margin - overscroll.x() - em_width)
1569                }
1570                SoftWrap::Column(column) => Some(column as f32 * em_advance),
1571            };
1572
1573            if view.set_wrap_width(wrap_width, cx) {
1574                view.snapshot(cx)
1575            } else {
1576                snapshot
1577            }
1578        });
1579
1580        let scroll_height = (snapshot.max_point().row() + 1) as f32 * line_height;
1581        if let EditorMode::AutoHeight { max_lines } = snapshot.mode {
1582            size.set_y(
1583                scroll_height
1584                    .min(constraint.max_along(Axis::Vertical))
1585                    .max(constraint.min_along(Axis::Vertical))
1586                    .min(line_height * max_lines as f32),
1587            )
1588        } else if let EditorMode::SingleLine = snapshot.mode {
1589            size.set_y(
1590                line_height
1591                    .min(constraint.max_along(Axis::Vertical))
1592                    .max(constraint.min_along(Axis::Vertical)),
1593            )
1594        } else if size.y().is_infinite() {
1595            size.set_y(scroll_height);
1596        }
1597        let gutter_size = vec2f(gutter_width, size.y());
1598        let text_size = vec2f(text_width, size.y());
1599
1600        let (autoscroll_horizontally, mut snapshot) = self.update_view(cx.app, |view, cx| {
1601            let autoscroll_horizontally = view.autoscroll_vertically(size.y(), line_height, cx);
1602            let snapshot = view.snapshot(cx);
1603            (autoscroll_horizontally, snapshot)
1604        });
1605
1606        let scroll_position = snapshot.scroll_position();
1607        // The scroll position is a fractional point, the whole number of which represents
1608        // the top of the window in terms of display rows.
1609        let start_row = scroll_position.y() as u32;
1610        let height_in_lines = size.y() / line_height;
1611        let max_row = snapshot.max_point().row();
1612
1613        // Add 1 to ensure selections bleed off screen
1614        let end_row = 1 + cmp::min(
1615            (scroll_position.y() + height_in_lines).ceil() as u32,
1616            max_row,
1617        );
1618
1619        let start_anchor = if start_row == 0 {
1620            Anchor::min()
1621        } else {
1622            snapshot
1623                .buffer_snapshot
1624                .anchor_before(DisplayPoint::new(start_row, 0).to_offset(&snapshot, Bias::Left))
1625        };
1626        let end_anchor = if end_row > max_row {
1627            Anchor::max()
1628        } else {
1629            snapshot
1630                .buffer_snapshot
1631                .anchor_before(DisplayPoint::new(end_row, 0).to_offset(&snapshot, Bias::Right))
1632        };
1633
1634        let mut selections: Vec<(ReplicaId, Vec<SelectionLayout>)> = Vec::new();
1635        let mut active_rows = BTreeMap::new();
1636        let mut highlighted_rows = None;
1637        let mut highlighted_ranges = Vec::new();
1638        let mut show_scrollbars = false;
1639        self.update_view(cx.app, |view, cx| {
1640            let display_map = view.display_map.update(cx, |map, cx| map.snapshot(cx));
1641
1642            highlighted_rows = view.highlighted_rows();
1643            let theme = cx.global::<Settings>().theme.as_ref();
1644            highlighted_ranges = view.background_highlights_in_range(
1645                start_anchor.clone()..end_anchor.clone(),
1646                &display_map,
1647                theme,
1648            );
1649
1650            let mut remote_selections = HashMap::default();
1651            for (replica_id, line_mode, selection) in display_map
1652                .buffer_snapshot
1653                .remote_selections_in_range(&(start_anchor.clone()..end_anchor.clone()))
1654            {
1655                // The local selections match the leader's selections.
1656                if Some(replica_id) == view.leader_replica_id {
1657                    continue;
1658                }
1659                remote_selections
1660                    .entry(replica_id)
1661                    .or_insert(Vec::new())
1662                    .push(SelectionLayout::new(selection, line_mode, &display_map));
1663            }
1664            selections.extend(remote_selections);
1665
1666            if view.show_local_selections {
1667                let mut local_selections = view
1668                    .selections
1669                    .disjoint_in_range(start_anchor..end_anchor, cx);
1670                local_selections.extend(view.selections.pending(cx));
1671                for selection in &local_selections {
1672                    let is_empty = selection.start == selection.end;
1673                    let selection_start = snapshot.prev_line_boundary(selection.start).1;
1674                    let selection_end = snapshot.next_line_boundary(selection.end).1;
1675                    for row in cmp::max(selection_start.row(), start_row)
1676                        ..=cmp::min(selection_end.row(), end_row)
1677                    {
1678                        let contains_non_empty_selection =
1679                            active_rows.entry(row).or_insert(!is_empty);
1680                        *contains_non_empty_selection |= !is_empty;
1681                    }
1682                }
1683
1684                // Render the local selections in the leader's color when following.
1685                let local_replica_id = view
1686                    .leader_replica_id
1687                    .unwrap_or_else(|| view.replica_id(cx));
1688
1689                selections.push((
1690                    local_replica_id,
1691                    local_selections
1692                        .into_iter()
1693                        .map(|selection| {
1694                            SelectionLayout::new(selection, view.selections.line_mode, &display_map)
1695                        })
1696                        .collect(),
1697                ));
1698            }
1699
1700            show_scrollbars = view.show_scrollbars();
1701        });
1702
1703        let line_number_layouts =
1704            self.layout_line_numbers(start_row..end_row, &active_rows, &snapshot, cx);
1705
1706        let hunk_layouts = self.layout_git_gutters(start_row..end_row, &snapshot);
1707
1708        let scrollbar_row_range = scroll_position.y()..(scroll_position.y() + height_in_lines);
1709
1710        let mut max_visible_line_width = 0.0;
1711        let line_layouts = self.layout_lines(start_row..end_row, &snapshot, cx);
1712        for line in &line_layouts {
1713            if line.width() > max_visible_line_width {
1714                max_visible_line_width = line.width();
1715            }
1716        }
1717
1718        let style = self.style.clone();
1719        let longest_line_width = layout_line(
1720            snapshot.longest_row(),
1721            &snapshot,
1722            &style,
1723            cx.text_layout_cache,
1724        )
1725        .width();
1726        let scroll_width = longest_line_width.max(max_visible_line_width) + overscroll.x();
1727        let em_width = style.text.em_width(cx.font_cache);
1728        let (scroll_width, blocks) = self.layout_blocks(
1729            start_row..end_row,
1730            &snapshot,
1731            size.x(),
1732            scroll_width,
1733            gutter_padding,
1734            gutter_width,
1735            em_width,
1736            gutter_width + gutter_margin,
1737            line_height,
1738            &style,
1739            &line_layouts,
1740            cx,
1741        );
1742
1743        let scroll_max = vec2f(
1744            ((scroll_width - text_size.x()) / em_width).max(0.0),
1745            max_row as f32,
1746        );
1747
1748        self.update_view(cx.app, |view, cx| {
1749            let clamped = view.clamp_scroll_left(scroll_max.x());
1750
1751            let autoscrolled = if autoscroll_horizontally {
1752                view.autoscroll_horizontally(
1753                    start_row,
1754                    text_size.x(),
1755                    scroll_width,
1756                    em_width,
1757                    &line_layouts,
1758                    cx,
1759                )
1760            } else {
1761                false
1762            };
1763
1764            if clamped || autoscrolled {
1765                snapshot = view.snapshot(cx);
1766            }
1767        });
1768
1769        let mut context_menu = None;
1770        let mut code_actions_indicator = None;
1771        let mut hover = None;
1772        let mut mode = EditorMode::Full;
1773        cx.render(&self.view.upgrade(cx).unwrap(), |view, cx| {
1774            let newest_selection_head = view
1775                .selections
1776                .newest::<usize>(cx)
1777                .head()
1778                .to_display_point(&snapshot);
1779
1780            let style = view.style(cx);
1781            if (start_row..end_row).contains(&newest_selection_head.row()) {
1782                if view.context_menu_visible() {
1783                    context_menu =
1784                        view.render_context_menu(newest_selection_head, style.clone(), cx);
1785                }
1786
1787                code_actions_indicator = view
1788                    .render_code_actions_indicator(&style, cx)
1789                    .map(|indicator| (newest_selection_head.row(), indicator));
1790            }
1791
1792            let visible_rows = start_row..start_row + line_layouts.len() as u32;
1793            hover = view.hover_state.render(&snapshot, &style, visible_rows, cx);
1794            mode = view.mode;
1795        });
1796
1797        if let Some((_, context_menu)) = context_menu.as_mut() {
1798            context_menu.layout(
1799                SizeConstraint {
1800                    min: Vector2F::zero(),
1801                    max: vec2f(
1802                        cx.window_size.x() * 0.7,
1803                        (12. * line_height).min((size.y() - line_height) / 2.),
1804                    ),
1805                },
1806                cx,
1807            );
1808        }
1809
1810        if let Some((_, indicator)) = code_actions_indicator.as_mut() {
1811            indicator.layout(
1812                SizeConstraint::strict_along(
1813                    Axis::Vertical,
1814                    line_height * style.code_actions.vertical_scale,
1815                ),
1816                cx,
1817            );
1818        }
1819
1820        if let Some((_, hover_popovers)) = hover.as_mut() {
1821            for hover_popover in hover_popovers.iter_mut() {
1822                hover_popover.layout(
1823                    SizeConstraint {
1824                        min: Vector2F::zero(),
1825                        max: vec2f(
1826                            (120. * em_width) // Default size
1827                                .min(size.x() / 2.) // Shrink to half of the editor width
1828                                .max(MIN_POPOVER_CHARACTER_WIDTH * em_width), // Apply minimum width of 20 characters
1829                            (16. * line_height) // Default size
1830                                .min(size.y() / 2.) // Shrink to half of the editor height
1831                                .max(MIN_POPOVER_LINE_HEIGHT * line_height), // Apply minimum height of 4 lines
1832                        ),
1833                    },
1834                    cx,
1835                );
1836            }
1837        }
1838
1839        (
1840            size,
1841            LayoutState {
1842                mode,
1843                position_map: Arc::new(PositionMap {
1844                    size,
1845                    scroll_max,
1846                    line_layouts,
1847                    line_height,
1848                    em_width,
1849                    em_advance,
1850                    snapshot,
1851                }),
1852                visible_display_row_range: start_row..end_row,
1853                gutter_size,
1854                gutter_padding,
1855                text_size,
1856                scrollbar_row_range,
1857                show_scrollbars,
1858                max_row,
1859                gutter_margin,
1860                active_rows,
1861                highlighted_rows,
1862                highlighted_ranges,
1863                line_number_layouts,
1864                hunk_layouts,
1865                blocks,
1866                selections,
1867                context_menu,
1868                code_actions_indicator,
1869                hover_popovers: hover,
1870            },
1871        )
1872    }
1873
1874    fn paint(
1875        &mut self,
1876        bounds: RectF,
1877        visible_bounds: RectF,
1878        layout: &mut Self::LayoutState,
1879        cx: &mut PaintContext,
1880    ) -> Self::PaintState {
1881        let visible_bounds = bounds.intersection(visible_bounds).unwrap_or_default();
1882        cx.scene.push_layer(Some(visible_bounds));
1883
1884        let gutter_bounds = RectF::new(bounds.origin(), layout.gutter_size);
1885        let text_bounds = RectF::new(
1886            bounds.origin() + vec2f(layout.gutter_size.x(), 0.0),
1887            layout.text_size,
1888        );
1889
1890        Self::attach_mouse_handlers(
1891            &self.view,
1892            &layout.position_map,
1893            visible_bounds,
1894            text_bounds,
1895            gutter_bounds,
1896            bounds,
1897            cx,
1898        );
1899
1900        self.paint_background(gutter_bounds, text_bounds, layout, cx);
1901        if layout.gutter_size.x() > 0. {
1902            self.paint_gutter(gutter_bounds, visible_bounds, layout, cx);
1903        }
1904        self.paint_text(text_bounds, visible_bounds, layout, cx);
1905
1906        cx.scene.push_layer(Some(bounds));
1907        if !layout.blocks.is_empty() {
1908            self.paint_blocks(bounds, visible_bounds, layout, cx);
1909        }
1910        self.paint_scrollbar(bounds, layout, cx);
1911        cx.scene.pop_layer();
1912
1913        cx.scene.pop_layer();
1914    }
1915
1916    fn dispatch_event(
1917        &mut self,
1918        event: &Event,
1919        _: RectF,
1920        _: RectF,
1921        _: &mut LayoutState,
1922        _: &mut (),
1923        cx: &mut EventContext,
1924    ) -> bool {
1925        if let Event::ModifiersChanged(event) = event {
1926            self.modifiers_changed(*event, cx);
1927        }
1928
1929        false
1930    }
1931
1932    fn rect_for_text_range(
1933        &self,
1934        range_utf16: Range<usize>,
1935        bounds: RectF,
1936        _: RectF,
1937        layout: &Self::LayoutState,
1938        _: &Self::PaintState,
1939        _: &gpui::MeasurementContext,
1940    ) -> Option<RectF> {
1941        let text_bounds = RectF::new(
1942            bounds.origin() + vec2f(layout.gutter_size.x(), 0.0),
1943            layout.text_size,
1944        );
1945        let content_origin = text_bounds.origin() + vec2f(layout.gutter_margin, 0.);
1946        let scroll_position = layout.position_map.snapshot.scroll_position();
1947        let start_row = scroll_position.y() as u32;
1948        let scroll_top = scroll_position.y() * layout.position_map.line_height;
1949        let scroll_left = scroll_position.x() * layout.position_map.em_width;
1950
1951        let range_start = OffsetUtf16(range_utf16.start)
1952            .to_display_point(&layout.position_map.snapshot.display_snapshot);
1953        if range_start.row() < start_row {
1954            return None;
1955        }
1956
1957        let line = layout
1958            .position_map
1959            .line_layouts
1960            .get((range_start.row() - start_row) as usize)?;
1961        let range_start_x = line.x_for_index(range_start.column() as usize);
1962        let range_start_y = range_start.row() as f32 * layout.position_map.line_height;
1963        Some(RectF::new(
1964            content_origin
1965                + vec2f(
1966                    range_start_x,
1967                    range_start_y + layout.position_map.line_height,
1968                )
1969                - vec2f(scroll_left, scroll_top),
1970            vec2f(
1971                layout.position_map.em_width,
1972                layout.position_map.line_height,
1973            ),
1974        ))
1975    }
1976
1977    fn debug(
1978        &self,
1979        bounds: RectF,
1980        _: &Self::LayoutState,
1981        _: &Self::PaintState,
1982        _: &gpui::DebugContext,
1983    ) -> json::Value {
1984        json!({
1985            "type": "BufferElement",
1986            "bounds": bounds.to_json()
1987        })
1988    }
1989}
1990
1991pub struct LayoutState {
1992    position_map: Arc<PositionMap>,
1993    gutter_size: Vector2F,
1994    gutter_padding: f32,
1995    gutter_margin: f32,
1996    text_size: Vector2F,
1997    mode: EditorMode,
1998    visible_display_row_range: Range<u32>,
1999    active_rows: BTreeMap<u32, bool>,
2000    highlighted_rows: Option<Range<u32>>,
2001    line_number_layouts: Vec<Option<text_layout::Line>>,
2002    hunk_layouts: Vec<DiffHunkLayout>,
2003    blocks: Vec<BlockLayout>,
2004    highlighted_ranges: Vec<(Range<DisplayPoint>, Color)>,
2005    selections: Vec<(ReplicaId, Vec<SelectionLayout>)>,
2006    scrollbar_row_range: Range<f32>,
2007    show_scrollbars: bool,
2008    max_row: u32,
2009    context_menu: Option<(DisplayPoint, ElementBox)>,
2010    code_actions_indicator: Option<(u32, ElementBox)>,
2011    hover_popovers: Option<(DisplayPoint, Vec<ElementBox>)>,
2012}
2013
2014pub struct PositionMap {
2015    size: Vector2F,
2016    line_height: f32,
2017    scroll_max: Vector2F,
2018    em_width: f32,
2019    em_advance: f32,
2020    line_layouts: Vec<text_layout::Line>,
2021    snapshot: EditorSnapshot,
2022}
2023
2024impl PositionMap {
2025    /// Returns two display points:
2026    /// 1. The nearest *valid* position in the editor
2027    /// 2. An unclipped, potentially *invalid* position that maps directly to
2028    ///    the given pixel position.
2029    fn point_for_position(
2030        &self,
2031        text_bounds: RectF,
2032        position: Vector2F,
2033    ) -> (DisplayPoint, DisplayPoint) {
2034        let scroll_position = self.snapshot.scroll_position();
2035        let position = position - text_bounds.origin();
2036        let y = position.y().max(0.0).min(self.size.y());
2037        let x = position.x() + (scroll_position.x() * self.em_width);
2038        let row = (y / self.line_height + scroll_position.y()) as u32;
2039        let (column, x_overshoot) = if let Some(line) = self
2040            .line_layouts
2041            .get(row as usize - scroll_position.y() as usize)
2042        {
2043            if let Some(ix) = line.index_for_x(x) {
2044                (ix as u32, 0.0)
2045            } else {
2046                (line.len() as u32, 0f32.max(x - line.width()))
2047            }
2048        } else {
2049            (0, x)
2050        };
2051
2052        let mut target_point = DisplayPoint::new(row, column);
2053        let point = self.snapshot.clip_point(target_point, Bias::Left);
2054        *target_point.column_mut() += (x_overshoot / self.em_advance) as u32;
2055
2056        (point, target_point)
2057    }
2058}
2059
2060struct BlockLayout {
2061    row: u32,
2062    element: ElementBox,
2063    style: BlockStyle,
2064}
2065
2066fn layout_line(
2067    row: u32,
2068    snapshot: &EditorSnapshot,
2069    style: &EditorStyle,
2070    layout_cache: &TextLayoutCache,
2071) -> text_layout::Line {
2072    let mut line = snapshot.line(row);
2073
2074    if line.len() > MAX_LINE_LEN {
2075        let mut len = MAX_LINE_LEN;
2076        while !line.is_char_boundary(len) {
2077            len -= 1;
2078        }
2079
2080        line.truncate(len);
2081    }
2082
2083    layout_cache.layout_str(
2084        &line,
2085        style.text.font_size,
2086        &[(
2087            snapshot.line_len(row) as usize,
2088            RunStyle {
2089                font_id: style.text.font_id,
2090                color: Color::black(),
2091                underline: Default::default(),
2092            },
2093        )],
2094    )
2095}
2096
2097#[derive(Copy, Clone, PartialEq, Eq, Debug)]
2098pub enum CursorShape {
2099    Bar,
2100    Block,
2101    Underscore,
2102    Hollow,
2103}
2104
2105impl Default for CursorShape {
2106    fn default() -> Self {
2107        CursorShape::Bar
2108    }
2109}
2110
2111#[derive(Debug)]
2112pub struct Cursor {
2113    origin: Vector2F,
2114    block_width: f32,
2115    line_height: f32,
2116    color: Color,
2117    shape: CursorShape,
2118    block_text: Option<Line>,
2119}
2120
2121impl Cursor {
2122    pub fn new(
2123        origin: Vector2F,
2124        block_width: f32,
2125        line_height: f32,
2126        color: Color,
2127        shape: CursorShape,
2128        block_text: Option<Line>,
2129    ) -> Cursor {
2130        Cursor {
2131            origin,
2132            block_width,
2133            line_height,
2134            color,
2135            shape,
2136            block_text,
2137        }
2138    }
2139
2140    pub fn bounding_rect(&self, origin: Vector2F) -> RectF {
2141        RectF::new(
2142            self.origin + origin,
2143            vec2f(self.block_width, self.line_height),
2144        )
2145    }
2146
2147    pub fn paint(&self, origin: Vector2F, cx: &mut PaintContext) {
2148        let bounds = match self.shape {
2149            CursorShape::Bar => RectF::new(self.origin + origin, vec2f(2.0, self.line_height)),
2150            CursorShape::Block | CursorShape::Hollow => RectF::new(
2151                self.origin + origin,
2152                vec2f(self.block_width, self.line_height),
2153            ),
2154            CursorShape::Underscore => RectF::new(
2155                self.origin + origin + Vector2F::new(0.0, self.line_height - 2.0),
2156                vec2f(self.block_width, 2.0),
2157            ),
2158        };
2159
2160        //Draw background or border quad
2161        if matches!(self.shape, CursorShape::Hollow) {
2162            cx.scene.push_quad(Quad {
2163                bounds,
2164                background: None,
2165                border: Border::all(1., self.color),
2166                corner_radius: 0.,
2167            });
2168        } else {
2169            cx.scene.push_quad(Quad {
2170                bounds,
2171                background: Some(self.color),
2172                border: Default::default(),
2173                corner_radius: 0.,
2174            });
2175        }
2176
2177        if let Some(block_text) = &self.block_text {
2178            block_text.paint(self.origin + origin, bounds, self.line_height, cx);
2179        }
2180    }
2181
2182    pub fn shape(&self) -> CursorShape {
2183        self.shape
2184    }
2185}
2186
2187#[derive(Debug)]
2188pub struct HighlightedRange {
2189    pub start_y: f32,
2190    pub line_height: f32,
2191    pub lines: Vec<HighlightedRangeLine>,
2192    pub color: Color,
2193    pub corner_radius: f32,
2194}
2195
2196#[derive(Debug)]
2197pub struct HighlightedRangeLine {
2198    pub start_x: f32,
2199    pub end_x: f32,
2200}
2201
2202impl HighlightedRange {
2203    pub fn paint(&self, bounds: RectF, scene: &mut Scene) {
2204        if self.lines.len() >= 2 && self.lines[0].start_x > self.lines[1].end_x {
2205            self.paint_lines(self.start_y, &self.lines[0..1], bounds, scene);
2206            self.paint_lines(
2207                self.start_y + self.line_height,
2208                &self.lines[1..],
2209                bounds,
2210                scene,
2211            );
2212        } else {
2213            self.paint_lines(self.start_y, &self.lines, bounds, scene);
2214        }
2215    }
2216
2217    fn paint_lines(
2218        &self,
2219        start_y: f32,
2220        lines: &[HighlightedRangeLine],
2221        bounds: RectF,
2222        scene: &mut Scene,
2223    ) {
2224        if lines.is_empty() {
2225            return;
2226        }
2227
2228        let mut path = PathBuilder::new();
2229        let first_line = lines.first().unwrap();
2230        let last_line = lines.last().unwrap();
2231
2232        let first_top_left = vec2f(first_line.start_x, start_y);
2233        let first_top_right = vec2f(first_line.end_x, start_y);
2234
2235        let curve_height = vec2f(0., self.corner_radius);
2236        let curve_width = |start_x: f32, end_x: f32| {
2237            let max = (end_x - start_x) / 2.;
2238            let width = if max < self.corner_radius {
2239                max
2240            } else {
2241                self.corner_radius
2242            };
2243
2244            vec2f(width, 0.)
2245        };
2246
2247        let top_curve_width = curve_width(first_line.start_x, first_line.end_x);
2248        path.reset(first_top_right - top_curve_width);
2249        path.curve_to(first_top_right + curve_height, first_top_right);
2250
2251        let mut iter = lines.iter().enumerate().peekable();
2252        while let Some((ix, line)) = iter.next() {
2253            let bottom_right = vec2f(line.end_x, start_y + (ix + 1) as f32 * self.line_height);
2254
2255            if let Some((_, next_line)) = iter.peek() {
2256                let next_top_right = vec2f(next_line.end_x, bottom_right.y());
2257
2258                match next_top_right.x().partial_cmp(&bottom_right.x()).unwrap() {
2259                    Ordering::Equal => {
2260                        path.line_to(bottom_right);
2261                    }
2262                    Ordering::Less => {
2263                        let curve_width = curve_width(next_top_right.x(), bottom_right.x());
2264                        path.line_to(bottom_right - curve_height);
2265                        if self.corner_radius > 0. {
2266                            path.curve_to(bottom_right - curve_width, bottom_right);
2267                        }
2268                        path.line_to(next_top_right + curve_width);
2269                        if self.corner_radius > 0. {
2270                            path.curve_to(next_top_right + curve_height, next_top_right);
2271                        }
2272                    }
2273                    Ordering::Greater => {
2274                        let curve_width = curve_width(bottom_right.x(), next_top_right.x());
2275                        path.line_to(bottom_right - curve_height);
2276                        if self.corner_radius > 0. {
2277                            path.curve_to(bottom_right + curve_width, bottom_right);
2278                        }
2279                        path.line_to(next_top_right - curve_width);
2280                        if self.corner_radius > 0. {
2281                            path.curve_to(next_top_right + curve_height, next_top_right);
2282                        }
2283                    }
2284                }
2285            } else {
2286                let curve_width = curve_width(line.start_x, line.end_x);
2287                path.line_to(bottom_right - curve_height);
2288                if self.corner_radius > 0. {
2289                    path.curve_to(bottom_right - curve_width, bottom_right);
2290                }
2291
2292                let bottom_left = vec2f(line.start_x, bottom_right.y());
2293                path.line_to(bottom_left + curve_width);
2294                if self.corner_radius > 0. {
2295                    path.curve_to(bottom_left - curve_height, bottom_left);
2296                }
2297            }
2298        }
2299
2300        if first_line.start_x > last_line.start_x {
2301            let curve_width = curve_width(last_line.start_x, first_line.start_x);
2302            let second_top_left = vec2f(last_line.start_x, start_y + self.line_height);
2303            path.line_to(second_top_left + curve_height);
2304            if self.corner_radius > 0. {
2305                path.curve_to(second_top_left + curve_width, second_top_left);
2306            }
2307            let first_bottom_left = vec2f(first_line.start_x, second_top_left.y());
2308            path.line_to(first_bottom_left - curve_width);
2309            if self.corner_radius > 0. {
2310                path.curve_to(first_bottom_left - curve_height, first_bottom_left);
2311            }
2312        }
2313
2314        path.line_to(first_top_left + curve_height);
2315        if self.corner_radius > 0. {
2316            path.curve_to(first_top_left + top_curve_width, first_top_left);
2317        }
2318        path.line_to(first_top_right - top_curve_width);
2319
2320        scene.push_path(path.build(self.color, Some(bounds)));
2321    }
2322}
2323
2324pub fn scale_vertical_mouse_autoscroll_delta(delta: f32) -> f32 {
2325    delta.powf(1.5) / 100.0
2326}
2327
2328fn scale_horizontal_mouse_autoscroll_delta(delta: f32) -> f32 {
2329    delta.powf(1.2) / 300.0
2330}
2331
2332#[cfg(test)]
2333mod tests {
2334    use std::sync::Arc;
2335
2336    use super::*;
2337    use crate::{
2338        display_map::{BlockDisposition, BlockProperties},
2339        Editor, MultiBuffer,
2340    };
2341    use settings::Settings;
2342    use util::test::sample_text;
2343
2344    #[gpui::test]
2345    fn test_layout_line_numbers(cx: &mut gpui::MutableAppContext) {
2346        cx.set_global(Settings::test(cx));
2347        let buffer = MultiBuffer::build_simple(&sample_text(6, 6, 'a'), cx);
2348        let (window_id, editor) = cx.add_window(Default::default(), |cx| {
2349            Editor::new(EditorMode::Full, buffer, None, None, cx)
2350        });
2351        let element = EditorElement::new(
2352            editor.downgrade(),
2353            editor.read(cx).style(cx),
2354            CursorShape::Bar,
2355        );
2356
2357        let layouts = editor.update(cx, |editor, cx| {
2358            let snapshot = editor.snapshot(cx);
2359            let mut presenter = cx.build_presenter(window_id, 30., Default::default());
2360            let layout_cx = presenter.build_layout_context(Vector2F::zero(), false, cx);
2361            element.layout_line_numbers(0..6, &Default::default(), &snapshot, &layout_cx)
2362        });
2363        assert_eq!(layouts.len(), 6);
2364    }
2365
2366    #[gpui::test]
2367    fn test_layout_with_placeholder_text_and_blocks(cx: &mut gpui::MutableAppContext) {
2368        cx.set_global(Settings::test(cx));
2369        let buffer = MultiBuffer::build_simple("", cx);
2370        let (window_id, editor) = cx.add_window(Default::default(), |cx| {
2371            Editor::new(EditorMode::Full, buffer, None, None, cx)
2372        });
2373
2374        editor.update(cx, |editor, cx| {
2375            editor.set_placeholder_text("hello", cx);
2376            editor.insert_blocks(
2377                [BlockProperties {
2378                    style: BlockStyle::Fixed,
2379                    disposition: BlockDisposition::Above,
2380                    height: 3,
2381                    position: Anchor::min(),
2382                    render: Arc::new(|_| Empty::new().boxed()),
2383                }],
2384                cx,
2385            );
2386
2387            // Blur the editor so that it displays placeholder text.
2388            cx.blur();
2389        });
2390
2391        let mut element = EditorElement::new(
2392            editor.downgrade(),
2393            editor.read(cx).style(cx),
2394            CursorShape::Bar,
2395        );
2396
2397        let mut scene = Scene::new(1.0);
2398        let mut presenter = cx.build_presenter(window_id, 30., Default::default());
2399        let mut layout_cx = presenter.build_layout_context(Vector2F::zero(), false, cx);
2400        let (size, mut state) = element.layout(
2401            SizeConstraint::new(vec2f(500., 500.), vec2f(500., 500.)),
2402            &mut layout_cx,
2403        );
2404
2405        assert_eq!(state.position_map.line_layouts.len(), 4);
2406        assert_eq!(
2407            state
2408                .line_number_layouts
2409                .iter()
2410                .map(Option::is_some)
2411                .collect::<Vec<_>>(),
2412            &[false, false, false, true]
2413        );
2414
2415        // Don't panic.
2416        let bounds = RectF::new(Default::default(), size);
2417        let mut paint_cx = presenter.build_paint_context(&mut scene, bounds.size(), cx);
2418        element.paint(bounds, bounds, &mut state, &mut paint_cx);
2419    }
2420}