element.rs

   1use super::{
   2    display_map::{BlockContext, ToDisplayPoint},
   3    Anchor, DisplayPoint, Editor, EditorMode, EditorSnapshot, Input, Scroll, Select, SelectPhase,
   4    SoftWrap, ToPoint, MAX_LINE_LEN,
   5};
   6use crate::{display_map::TransformBlock, EditorStyle};
   7use clock::ReplicaId;
   8use collections::{BTreeMap, HashMap};
   9use gpui::{
  10    color::Color,
  11    elements::*,
  12    fonts::{HighlightStyle, Underline},
  13    geometry::{
  14        rect::RectF,
  15        vector::{vec2f, Vector2F},
  16        PathBuilder,
  17    },
  18    json::{self, ToJson},
  19    text_layout::{self, Line, RunStyle, TextLayoutCache},
  20    AppContext, Axis, Border, Element, ElementBox, Event, EventContext, LayoutContext,
  21    MutableAppContext, PaintContext, Quad, Scene, SizeConstraint, ViewContext, WeakViewHandle,
  22};
  23use json::json;
  24use language::Bias;
  25use smallvec::SmallVec;
  26use std::{
  27    cmp::{self, Ordering},
  28    fmt::Write,
  29    ops::Range,
  30};
  31
  32pub struct EditorElement {
  33    view: WeakViewHandle<Editor>,
  34    style: EditorStyle,
  35    cursor_shape: CursorShape,
  36}
  37
  38impl EditorElement {
  39    pub fn new(
  40        view: WeakViewHandle<Editor>,
  41        style: EditorStyle,
  42        cursor_shape: CursorShape,
  43    ) -> Self {
  44        Self {
  45            view,
  46            style,
  47            cursor_shape,
  48        }
  49    }
  50
  51    fn view<'a>(&self, cx: &'a AppContext) -> &'a Editor {
  52        self.view.upgrade(cx).unwrap().read(cx)
  53    }
  54
  55    fn update_view<F, T>(&self, cx: &mut MutableAppContext, f: F) -> T
  56    where
  57        F: FnOnce(&mut Editor, &mut ViewContext<Editor>) -> T,
  58    {
  59        self.view.upgrade(cx).unwrap().update(cx, f)
  60    }
  61
  62    fn snapshot(&self, cx: &mut MutableAppContext) -> EditorSnapshot {
  63        self.update_view(cx, |view, cx| view.snapshot(cx))
  64    }
  65
  66    fn mouse_down(
  67        &self,
  68        position: Vector2F,
  69        alt: bool,
  70        shift: bool,
  71        mut click_count: usize,
  72        layout: &mut LayoutState,
  73        paint: &mut PaintState,
  74        cx: &mut EventContext,
  75    ) -> bool {
  76        if paint.gutter_bounds.contains_point(position) {
  77            click_count = 3; // Simulate triple-click when clicking the gutter to select lines
  78        } else if !paint.text_bounds.contains_point(position) {
  79            return false;
  80        }
  81
  82        let snapshot = self.snapshot(cx.app);
  83        let (position, overshoot) = paint.point_for_position(&snapshot, layout, position);
  84
  85        if shift && alt {
  86            cx.dispatch_action(Select(SelectPhase::BeginColumnar {
  87                position,
  88                overshoot,
  89            }));
  90        } else if shift {
  91            cx.dispatch_action(Select(SelectPhase::Extend {
  92                position,
  93                click_count,
  94            }));
  95        } else {
  96            cx.dispatch_action(Select(SelectPhase::Begin {
  97                position,
  98                add: alt,
  99                click_count,
 100            }));
 101        }
 102
 103        true
 104    }
 105
 106    fn mouse_up(&self, _position: Vector2F, cx: &mut EventContext) -> bool {
 107        if self.view(cx.app.as_ref()).is_selecting() {
 108            cx.dispatch_action(Select(SelectPhase::End));
 109            true
 110        } else {
 111            false
 112        }
 113    }
 114
 115    fn mouse_dragged(
 116        &self,
 117        position: Vector2F,
 118        layout: &mut LayoutState,
 119        paint: &mut PaintState,
 120        cx: &mut EventContext,
 121    ) -> bool {
 122        let view = self.view(cx.app.as_ref());
 123
 124        if view.is_selecting() {
 125            let rect = paint.text_bounds;
 126            let mut scroll_delta = Vector2F::zero();
 127
 128            let vertical_margin = layout.line_height.min(rect.height() / 3.0);
 129            let top = rect.origin_y() + vertical_margin;
 130            let bottom = rect.lower_left().y() - vertical_margin;
 131            if position.y() < top {
 132                scroll_delta.set_y(-scale_vertical_mouse_autoscroll_delta(top - position.y()))
 133            }
 134            if position.y() > bottom {
 135                scroll_delta.set_y(scale_vertical_mouse_autoscroll_delta(position.y() - bottom))
 136            }
 137
 138            let horizontal_margin = layout.line_height.min(rect.width() / 3.0);
 139            let left = rect.origin_x() + horizontal_margin;
 140            let right = rect.upper_right().x() - horizontal_margin;
 141            if position.x() < left {
 142                scroll_delta.set_x(-scale_horizontal_mouse_autoscroll_delta(
 143                    left - position.x(),
 144                ))
 145            }
 146            if position.x() > right {
 147                scroll_delta.set_x(scale_horizontal_mouse_autoscroll_delta(
 148                    position.x() - right,
 149                ))
 150            }
 151
 152            let snapshot = self.snapshot(cx.app);
 153            let (position, overshoot) = paint.point_for_position(&snapshot, layout, position);
 154
 155            cx.dispatch_action(Select(SelectPhase::Update {
 156                position,
 157                overshoot,
 158                scroll_position: (snapshot.scroll_position() + scroll_delta)
 159                    .clamp(Vector2F::zero(), layout.scroll_max),
 160            }));
 161            true
 162        } else {
 163            false
 164        }
 165    }
 166
 167    fn key_down(&self, input: Option<&str>, cx: &mut EventContext) -> bool {
 168        let view = self.view.upgrade(cx.app).unwrap();
 169
 170        if view.is_focused(cx.app) {
 171            if let Some(input) = input {
 172                cx.dispatch_action(Input(input.to_string()));
 173                true
 174            } else {
 175                false
 176            }
 177        } else {
 178            false
 179        }
 180    }
 181
 182    fn scroll(
 183        &self,
 184        position: Vector2F,
 185        mut delta: Vector2F,
 186        precise: bool,
 187        layout: &mut LayoutState,
 188        paint: &mut PaintState,
 189        cx: &mut EventContext,
 190    ) -> bool {
 191        if !paint.bounds.contains_point(position) {
 192            return false;
 193        }
 194
 195        let snapshot = self.snapshot(cx.app);
 196        let max_glyph_width = layout.em_width;
 197        if !precise {
 198            delta *= vec2f(max_glyph_width, layout.line_height);
 199        }
 200
 201        let scroll_position = snapshot.scroll_position();
 202        let x = (scroll_position.x() * max_glyph_width - delta.x()) / max_glyph_width;
 203        let y = (scroll_position.y() * layout.line_height - delta.y()) / layout.line_height;
 204        let scroll_position = vec2f(x, y).clamp(Vector2F::zero(), layout.scroll_max);
 205
 206        cx.dispatch_action(Scroll(scroll_position));
 207
 208        true
 209    }
 210
 211    fn paint_background(
 212        &self,
 213        gutter_bounds: RectF,
 214        text_bounds: RectF,
 215        layout: &LayoutState,
 216        cx: &mut PaintContext,
 217    ) {
 218        let bounds = gutter_bounds.union_rect(text_bounds);
 219        let scroll_top = layout.snapshot.scroll_position().y() * layout.line_height;
 220        let editor = self.view(cx.app);
 221        cx.scene.push_quad(Quad {
 222            bounds: gutter_bounds,
 223            background: Some(self.style.gutter_background),
 224            border: Border::new(0., Color::transparent_black()),
 225            corner_radius: 0.,
 226        });
 227        cx.scene.push_quad(Quad {
 228            bounds: text_bounds,
 229            background: Some(self.style.background),
 230            border: Border::new(0., Color::transparent_black()),
 231            corner_radius: 0.,
 232        });
 233
 234        if let EditorMode::Full = editor.mode {
 235            let mut active_rows = layout.active_rows.iter().peekable();
 236            while let Some((start_row, contains_non_empty_selection)) = active_rows.next() {
 237                let mut end_row = *start_row;
 238                while active_rows.peek().map_or(false, |r| {
 239                    *r.0 == end_row + 1 && r.1 == contains_non_empty_selection
 240                }) {
 241                    active_rows.next().unwrap();
 242                    end_row += 1;
 243                }
 244
 245                if !contains_non_empty_selection {
 246                    let origin = vec2f(
 247                        bounds.origin_x(),
 248                        bounds.origin_y() + (layout.line_height * *start_row as f32) - scroll_top,
 249                    );
 250                    let size = vec2f(
 251                        bounds.width(),
 252                        layout.line_height * (end_row - start_row + 1) as f32,
 253                    );
 254                    cx.scene.push_quad(Quad {
 255                        bounds: RectF::new(origin, size),
 256                        background: Some(self.style.active_line_background),
 257                        border: Border::default(),
 258                        corner_radius: 0.,
 259                    });
 260                }
 261            }
 262
 263            if let Some(highlighted_rows) = &layout.highlighted_rows {
 264                let origin = vec2f(
 265                    bounds.origin_x(),
 266                    bounds.origin_y() + (layout.line_height * highlighted_rows.start as f32)
 267                        - scroll_top,
 268                );
 269                let size = vec2f(
 270                    bounds.width(),
 271                    layout.line_height * highlighted_rows.len() as f32,
 272                );
 273                cx.scene.push_quad(Quad {
 274                    bounds: RectF::new(origin, size),
 275                    background: Some(self.style.highlighted_line_background),
 276                    border: Border::default(),
 277                    corner_radius: 0.,
 278                });
 279            }
 280        }
 281    }
 282
 283    fn paint_gutter(
 284        &mut self,
 285        bounds: RectF,
 286        visible_bounds: RectF,
 287        layout: &mut LayoutState,
 288        cx: &mut PaintContext,
 289    ) {
 290        let scroll_top = layout.snapshot.scroll_position().y() * layout.line_height;
 291        for (ix, line) in layout.line_number_layouts.iter().enumerate() {
 292            if let Some(line) = line {
 293                let line_origin = bounds.origin()
 294                    + vec2f(
 295                        bounds.width() - line.width() - layout.gutter_padding,
 296                        ix as f32 * layout.line_height - (scroll_top % layout.line_height),
 297                    );
 298                line.paint(line_origin, visible_bounds, layout.line_height, cx);
 299            }
 300        }
 301
 302        if let Some((row, indicator)) = layout.code_actions_indicator.as_mut() {
 303            let mut x = bounds.width() - layout.gutter_padding;
 304            let mut y = *row as f32 * layout.line_height - scroll_top;
 305            x += ((layout.gutter_padding + layout.gutter_margin) - indicator.size().x()) / 2.;
 306            y += (layout.line_height - indicator.size().y()) / 2.;
 307            indicator.paint(bounds.origin() + vec2f(x, y), visible_bounds, cx);
 308        }
 309    }
 310
 311    fn paint_text(
 312        &mut self,
 313        bounds: RectF,
 314        visible_bounds: RectF,
 315        layout: &mut LayoutState,
 316        cx: &mut PaintContext,
 317    ) {
 318        let view = self.view(cx.app);
 319        let style = &self.style;
 320        let local_replica_id = view.replica_id(cx);
 321        let scroll_position = layout.snapshot.scroll_position();
 322        let start_row = scroll_position.y() as u32;
 323        let scroll_top = scroll_position.y() * layout.line_height;
 324        let end_row = ((scroll_top + bounds.height()) / layout.line_height).ceil() as u32 + 1; // Add 1 to ensure selections bleed off screen
 325        let max_glyph_width = layout.em_width;
 326        let scroll_left = scroll_position.x() * max_glyph_width;
 327        let content_origin = bounds.origin() + vec2f(layout.gutter_margin, 0.);
 328
 329        cx.scene.push_layer(Some(bounds));
 330
 331        for (range, color) in &layout.highlighted_ranges {
 332            self.paint_highlighted_range(
 333                range.clone(),
 334                start_row,
 335                end_row,
 336                *color,
 337                0.,
 338                0.15 * layout.line_height,
 339                layout,
 340                content_origin,
 341                scroll_top,
 342                scroll_left,
 343                bounds,
 344                cx,
 345            );
 346        }
 347
 348        let mut cursors = SmallVec::<[Cursor; 32]>::new();
 349        for (replica_id, selections) in &layout.selections {
 350            let selection_style = style.replica_selection_style(*replica_id);
 351            let corner_radius = 0.15 * layout.line_height;
 352
 353            for selection in selections {
 354                self.paint_highlighted_range(
 355                    selection.start..selection.end,
 356                    start_row,
 357                    end_row,
 358                    selection_style.selection,
 359                    corner_radius,
 360                    corner_radius * 2.,
 361                    layout,
 362                    content_origin,
 363                    scroll_top,
 364                    scroll_left,
 365                    bounds,
 366                    cx,
 367                );
 368
 369                if view.show_local_cursors() || *replica_id != local_replica_id {
 370                    let cursor_position = selection.head();
 371                    if (start_row..end_row).contains(&cursor_position.row()) {
 372                        let cursor_row_layout =
 373                            &layout.line_layouts[(cursor_position.row() - start_row) as usize];
 374                        let cursor_column = cursor_position.column() as usize;
 375
 376                        let cursor_character_x = cursor_row_layout.x_for_index(cursor_column);
 377                        let mut block_width =
 378                            cursor_row_layout.x_for_index(cursor_column + 1) - cursor_character_x;
 379                        if block_width == 0.0 {
 380                            block_width = layout.em_width;
 381                        }
 382
 383                        let block_text =
 384                            if matches!(self.cursor_shape, CursorShape::Block) {
 385                                layout.snapshot.chars_at(cursor_position).next().and_then(
 386                                    |character| {
 387                                        let font_id =
 388                                            cursor_row_layout.font_for_index(cursor_column)?;
 389                                        let text = character.to_string();
 390
 391                                        Some(cx.text_layout_cache.layout_str(
 392                                            &text,
 393                                            cursor_row_layout.font_size(),
 394                                            &[(
 395                                                text.len(),
 396                                                RunStyle {
 397                                                    font_id,
 398                                                    color: style.background,
 399                                                    underline: None,
 400                                                },
 401                                            )],
 402                                        ))
 403                                    },
 404                                )
 405                            } else {
 406                                None
 407                            };
 408
 409                        let x = cursor_character_x - scroll_left;
 410                        let y = cursor_position.row() as f32 * layout.line_height - scroll_top;
 411                        cursors.push(Cursor {
 412                            color: selection_style.cursor,
 413                            block_width,
 414                            origin: content_origin + vec2f(x, y),
 415                            line_height: layout.line_height,
 416                            shape: self.cursor_shape,
 417                            block_text,
 418                        });
 419                    }
 420                }
 421            }
 422        }
 423
 424        if let Some(visible_text_bounds) = bounds.intersection(visible_bounds) {
 425            // Draw glyphs
 426            for (ix, line) in layout.line_layouts.iter().enumerate() {
 427                let row = start_row + ix as u32;
 428                line.paint(
 429                    content_origin
 430                        + vec2f(-scroll_left, row as f32 * layout.line_height - scroll_top),
 431                    visible_text_bounds,
 432                    layout.line_height,
 433                    cx,
 434                );
 435            }
 436        }
 437
 438        cx.scene.push_layer(Some(bounds));
 439        for cursor in cursors {
 440            cursor.paint(cx);
 441        }
 442        cx.scene.pop_layer();
 443
 444        if let Some((position, context_menu)) = layout.context_menu.as_mut() {
 445            cx.scene.push_stacking_context(None);
 446
 447            let cursor_row_layout = &layout.line_layouts[(position.row() - start_row) as usize];
 448            let x = cursor_row_layout.x_for_index(position.column() as usize) - scroll_left;
 449            let y = (position.row() + 1) as f32 * layout.line_height - scroll_top;
 450            let mut list_origin = content_origin + vec2f(x, y);
 451            let list_height = context_menu.size().y();
 452
 453            if list_origin.y() + list_height > bounds.lower_left().y() {
 454                list_origin.set_y(list_origin.y() - layout.line_height - list_height);
 455            }
 456
 457            context_menu.paint(
 458                list_origin,
 459                RectF::from_points(Vector2F::zero(), vec2f(f32::MAX, f32::MAX)), // Let content bleed outside of editor
 460                cx,
 461            );
 462
 463            cx.scene.pop_stacking_context();
 464        }
 465
 466        cx.scene.pop_layer();
 467    }
 468
 469    fn paint_highlighted_range(
 470        &self,
 471        range: Range<DisplayPoint>,
 472        start_row: u32,
 473        end_row: u32,
 474        color: Color,
 475        corner_radius: f32,
 476        line_end_overshoot: f32,
 477        layout: &LayoutState,
 478        content_origin: Vector2F,
 479        scroll_top: f32,
 480        scroll_left: f32,
 481        bounds: RectF,
 482        cx: &mut PaintContext,
 483    ) {
 484        if range.start != range.end {
 485            let row_range = if range.end.column() == 0 {
 486                cmp::max(range.start.row(), start_row)..cmp::min(range.end.row(), end_row)
 487            } else {
 488                cmp::max(range.start.row(), start_row)..cmp::min(range.end.row() + 1, end_row)
 489            };
 490
 491            let highlighted_range = HighlightedRange {
 492                color,
 493                line_height: layout.line_height,
 494                corner_radius,
 495                start_y: content_origin.y() + row_range.start as f32 * layout.line_height
 496                    - scroll_top,
 497                lines: row_range
 498                    .into_iter()
 499                    .map(|row| {
 500                        let line_layout = &layout.line_layouts[(row - start_row) as usize];
 501                        HighlightedRangeLine {
 502                            start_x: if row == range.start.row() {
 503                                content_origin.x()
 504                                    + line_layout.x_for_index(range.start.column() as usize)
 505                                    - scroll_left
 506                            } else {
 507                                content_origin.x() - scroll_left
 508                            },
 509                            end_x: if row == range.end.row() {
 510                                content_origin.x()
 511                                    + line_layout.x_for_index(range.end.column() as usize)
 512                                    - scroll_left
 513                            } else {
 514                                content_origin.x() + line_layout.width() + line_end_overshoot
 515                                    - scroll_left
 516                            },
 517                        }
 518                    })
 519                    .collect(),
 520            };
 521
 522            highlighted_range.paint(bounds, cx.scene);
 523        }
 524    }
 525
 526    fn paint_blocks(
 527        &mut self,
 528        bounds: RectF,
 529        visible_bounds: RectF,
 530        layout: &mut LayoutState,
 531        cx: &mut PaintContext,
 532    ) {
 533        let scroll_position = layout.snapshot.scroll_position();
 534        let scroll_left = scroll_position.x() * layout.em_width;
 535        let scroll_top = scroll_position.y() * layout.line_height;
 536
 537        for (row, element) in &mut layout.blocks {
 538            let origin = bounds.origin()
 539                + vec2f(-scroll_left, *row as f32 * layout.line_height - scroll_top);
 540            element.paint(origin, visible_bounds, cx);
 541        }
 542    }
 543
 544    fn max_line_number_width(&self, snapshot: &EditorSnapshot, cx: &LayoutContext) -> f32 {
 545        let digit_count = (snapshot.max_buffer_row() as f32).log10().floor() as usize + 1;
 546        let style = &self.style;
 547
 548        cx.text_layout_cache
 549            .layout_str(
 550                "1".repeat(digit_count).as_str(),
 551                style.text.font_size,
 552                &[(
 553                    digit_count,
 554                    RunStyle {
 555                        font_id: style.text.font_id,
 556                        color: Color::black(),
 557                        underline: None,
 558                    },
 559                )],
 560            )
 561            .width()
 562    }
 563
 564    fn layout_line_numbers(
 565        &self,
 566        rows: Range<u32>,
 567        active_rows: &BTreeMap<u32, bool>,
 568        snapshot: &EditorSnapshot,
 569        cx: &LayoutContext,
 570    ) -> Vec<Option<text_layout::Line>> {
 571        let style = &self.style;
 572        let include_line_numbers = snapshot.mode == EditorMode::Full;
 573        let mut line_number_layouts = Vec::with_capacity(rows.len());
 574        let mut line_number = String::new();
 575        for (ix, row) in snapshot
 576            .buffer_rows(rows.start)
 577            .take((rows.end - rows.start) as usize)
 578            .enumerate()
 579        {
 580            let display_row = rows.start + ix as u32;
 581            let color = if active_rows.contains_key(&display_row) {
 582                style.line_number_active
 583            } else {
 584                style.line_number
 585            };
 586            if let Some(buffer_row) = row {
 587                if include_line_numbers {
 588                    line_number.clear();
 589                    write!(&mut line_number, "{}", buffer_row + 1).unwrap();
 590                    line_number_layouts.push(Some(cx.text_layout_cache.layout_str(
 591                        &line_number,
 592                        style.text.font_size,
 593                        &[(
 594                            line_number.len(),
 595                            RunStyle {
 596                                font_id: style.text.font_id,
 597                                color,
 598                                underline: None,
 599                            },
 600                        )],
 601                    )));
 602                }
 603            } else {
 604                line_number_layouts.push(None);
 605            }
 606        }
 607
 608        line_number_layouts
 609    }
 610
 611    fn layout_lines(
 612        &mut self,
 613        mut rows: Range<u32>,
 614        snapshot: &mut EditorSnapshot,
 615        cx: &LayoutContext,
 616    ) -> Vec<text_layout::Line> {
 617        rows.end = cmp::min(rows.end, snapshot.max_point().row() + 1);
 618        if rows.start >= rows.end {
 619            return Vec::new();
 620        }
 621
 622        // When the editor is empty and unfocused, then show the placeholder.
 623        if snapshot.is_empty() && !snapshot.is_focused() {
 624            let placeholder_style = self
 625                .style
 626                .placeholder_text
 627                .as_ref()
 628                .unwrap_or_else(|| &self.style.text);
 629            let placeholder_text = snapshot.placeholder_text();
 630            let placeholder_lines = placeholder_text
 631                .as_ref()
 632                .map_or("", AsRef::as_ref)
 633                .split('\n')
 634                .skip(rows.start as usize)
 635                .take(rows.len());
 636            return placeholder_lines
 637                .map(|line| {
 638                    cx.text_layout_cache.layout_str(
 639                        line,
 640                        placeholder_style.font_size,
 641                        &[(
 642                            line.len(),
 643                            RunStyle {
 644                                font_id: placeholder_style.font_id,
 645                                color: placeholder_style.color,
 646                                underline: None,
 647                            },
 648                        )],
 649                    )
 650                })
 651                .collect();
 652        } else {
 653            let style = &self.style;
 654            let chunks = snapshot.chunks(rows.clone(), true).map(|chunk| {
 655                let mut highlight_style = chunk
 656                    .syntax_highlight_id
 657                    .and_then(|id| id.style(&style.syntax));
 658
 659                if let Some(chunk_highlight) = chunk.highlight_style {
 660                    if let Some(highlight_style) = highlight_style.as_mut() {
 661                        highlight_style.highlight(chunk_highlight);
 662                    } else {
 663                        highlight_style = Some(chunk_highlight);
 664                    }
 665                }
 666
 667                if let Some(severity) = chunk.diagnostic {
 668                    let diagnostic_style = super::diagnostic_style(severity, true, style);
 669                    let diagnostic_highlight = HighlightStyle {
 670                        underline: Some(Underline {
 671                            color: diagnostic_style.message.text.color,
 672                            thickness: 1.0.into(),
 673                            squiggly: true,
 674                        }),
 675                        ..Default::default()
 676                    };
 677
 678                    if let Some(highlight_style) = highlight_style.as_mut() {
 679                        highlight_style.highlight(diagnostic_highlight);
 680                    } else {
 681                        highlight_style = Some(diagnostic_highlight);
 682                    }
 683                }
 684
 685                (chunk.text, highlight_style)
 686            });
 687            layout_highlighted_chunks(
 688                chunks,
 689                &style.text,
 690                &cx.text_layout_cache,
 691                &cx.font_cache,
 692                MAX_LINE_LEN,
 693                rows.len() as usize,
 694            )
 695        }
 696    }
 697
 698    fn layout_blocks(
 699        &mut self,
 700        rows: Range<u32>,
 701        snapshot: &EditorSnapshot,
 702        width: f32,
 703        gutter_padding: f32,
 704        gutter_width: f32,
 705        em_width: f32,
 706        text_x: f32,
 707        line_height: f32,
 708        style: &EditorStyle,
 709        line_layouts: &[text_layout::Line],
 710        cx: &mut LayoutContext,
 711    ) -> Vec<(u32, ElementBox)> {
 712        let scroll_x = snapshot.scroll_position.x();
 713        snapshot
 714            .blocks_in_range(rows.clone())
 715            .map(|(block_row, block)| {
 716                let mut element = match block {
 717                    TransformBlock::Custom(block) => {
 718                        let align_to = block
 719                            .position()
 720                            .to_point(&snapshot.buffer_snapshot)
 721                            .to_display_point(snapshot);
 722                        let anchor_x = text_x
 723                            + if rows.contains(&align_to.row()) {
 724                                line_layouts[(align_to.row() - rows.start) as usize]
 725                                    .x_for_index(align_to.column() as usize)
 726                            } else {
 727                                layout_line(align_to.row(), snapshot, style, cx.text_layout_cache)
 728                                    .x_for_index(align_to.column() as usize)
 729                            };
 730
 731                        block.render(&BlockContext {
 732                            cx,
 733                            anchor_x,
 734                            gutter_padding,
 735                            line_height,
 736                            scroll_x,
 737                            gutter_width,
 738                            em_width,
 739                        })
 740                    }
 741                    TransformBlock::ExcerptHeader {
 742                        buffer,
 743                        starts_new_buffer,
 744                        ..
 745                    } => {
 746                        if *starts_new_buffer {
 747                            let style = &self.style.diagnostic_path_header;
 748                            let font_size =
 749                                (style.text_scale_factor * self.style.text.font_size).round();
 750
 751                            let mut filename = None;
 752                            let mut parent_path = None;
 753                            if let Some(path) = buffer.path() {
 754                                filename =
 755                                    path.file_name().map(|f| f.to_string_lossy().to_string());
 756                                parent_path =
 757                                    path.parent().map(|p| p.to_string_lossy().to_string() + "/");
 758                            }
 759
 760                            Flex::row()
 761                                .with_child(
 762                                    Label::new(
 763                                        filename.unwrap_or_else(|| "untitled".to_string()),
 764                                        style.filename.text.clone().with_font_size(font_size),
 765                                    )
 766                                    .contained()
 767                                    .with_style(style.filename.container)
 768                                    .boxed(),
 769                                )
 770                                .with_children(parent_path.map(|path| {
 771                                    Label::new(
 772                                        path,
 773                                        style.path.text.clone().with_font_size(font_size),
 774                                    )
 775                                    .contained()
 776                                    .with_style(style.path.container)
 777                                    .boxed()
 778                                }))
 779                                .aligned()
 780                                .left()
 781                                .contained()
 782                                .with_style(style.container)
 783                                .with_padding_left(gutter_padding + scroll_x * em_width)
 784                                .expanded()
 785                                .named("path header block")
 786                        } else {
 787                            let text_style = self.style.text.clone();
 788                            Label::new("".to_string(), text_style)
 789                                .contained()
 790                                .with_padding_left(gutter_padding + scroll_x * em_width)
 791                                .named("collapsed context")
 792                        }
 793                    }
 794                };
 795
 796                element.layout(
 797                    SizeConstraint {
 798                        min: Vector2F::zero(),
 799                        max: vec2f(width, block.height() as f32 * line_height),
 800                    },
 801                    cx,
 802                );
 803                (block_row, element)
 804            })
 805            .collect()
 806    }
 807}
 808
 809impl Element for EditorElement {
 810    type LayoutState = LayoutState;
 811    type PaintState = PaintState;
 812
 813    fn layout(
 814        &mut self,
 815        constraint: SizeConstraint,
 816        cx: &mut LayoutContext,
 817    ) -> (Vector2F, Self::LayoutState) {
 818        let mut size = constraint.max;
 819        if size.x().is_infinite() {
 820            unimplemented!("we don't yet handle an infinite width constraint on buffer elements");
 821        }
 822
 823        let snapshot = self.snapshot(cx.app);
 824        let style = self.style.clone();
 825        let line_height = style.text.line_height(cx.font_cache);
 826
 827        let gutter_padding;
 828        let gutter_width;
 829        let gutter_margin;
 830        if snapshot.mode == EditorMode::Full {
 831            gutter_padding = style.text.em_width(cx.font_cache) * style.gutter_padding_factor;
 832            gutter_width = self.max_line_number_width(&snapshot, cx) + gutter_padding * 2.0;
 833            gutter_margin = -style.text.descent(cx.font_cache);
 834        } else {
 835            gutter_padding = 0.0;
 836            gutter_width = 0.0;
 837            gutter_margin = 0.0;
 838        };
 839
 840        let text_width = size.x() - gutter_width;
 841        let em_width = style.text.em_width(cx.font_cache);
 842        let em_advance = style.text.em_advance(cx.font_cache);
 843        let overscroll = vec2f(em_width, 0.);
 844        let snapshot = self.update_view(cx.app, |view, cx| {
 845            let wrap_width = match view.soft_wrap_mode(cx) {
 846                SoftWrap::None => None,
 847                SoftWrap::EditorWidth => {
 848                    Some(text_width - gutter_margin - overscroll.x() - em_width)
 849                }
 850                SoftWrap::Column(column) => Some(column as f32 * em_advance),
 851            };
 852
 853            if view.set_wrap_width(wrap_width, cx) {
 854                view.snapshot(cx)
 855            } else {
 856                snapshot
 857            }
 858        });
 859
 860        let scroll_height = (snapshot.max_point().row() + 1) as f32 * line_height;
 861        if let EditorMode::AutoHeight { max_lines } = snapshot.mode {
 862            size.set_y(
 863                scroll_height
 864                    .min(constraint.max_along(Axis::Vertical))
 865                    .max(constraint.min_along(Axis::Vertical))
 866                    .min(line_height * max_lines as f32),
 867            )
 868        } else if size.y().is_infinite() {
 869            size.set_y(scroll_height);
 870        }
 871        let gutter_size = vec2f(gutter_width, size.y());
 872        let text_size = vec2f(text_width, size.y());
 873
 874        let (autoscroll_horizontally, mut snapshot) = self.update_view(cx.app, |view, cx| {
 875            let autoscroll_horizontally = view.autoscroll_vertically(size.y(), line_height, cx);
 876            let snapshot = view.snapshot(cx);
 877            (autoscroll_horizontally, snapshot)
 878        });
 879
 880        let scroll_position = snapshot.scroll_position();
 881        let start_row = scroll_position.y() as u32;
 882        let scroll_top = scroll_position.y() * line_height;
 883        let end_row = ((scroll_top + size.y()) / line_height).ceil() as u32 + 1; // Add 1 to ensure selections bleed off screen
 884
 885        let start_anchor = if start_row == 0 {
 886            Anchor::min()
 887        } else {
 888            snapshot
 889                .buffer_snapshot
 890                .anchor_before(DisplayPoint::new(start_row, 0).to_offset(&snapshot, Bias::Left))
 891        };
 892        let end_anchor = if end_row > snapshot.max_point().row() {
 893            Anchor::max()
 894        } else {
 895            snapshot
 896                .buffer_snapshot
 897                .anchor_before(DisplayPoint::new(end_row, 0).to_offset(&snapshot, Bias::Right))
 898        };
 899
 900        let mut selections = HashMap::default();
 901        let mut active_rows = BTreeMap::new();
 902        let mut highlighted_rows = None;
 903        let mut highlighted_ranges = Vec::new();
 904        self.update_view(cx.app, |view, cx| {
 905            let display_map = view.display_map.update(cx, |map, cx| map.snapshot(cx));
 906
 907            highlighted_rows = view.highlighted_rows();
 908            highlighted_ranges = view.background_highlights_in_range(
 909                start_anchor.clone()..end_anchor.clone(),
 910                &display_map,
 911            );
 912
 913            let local_selections = view
 914                .local_selections_in_range(start_anchor.clone()..end_anchor.clone(), &display_map);
 915            for selection in &local_selections {
 916                let is_empty = selection.start == selection.end;
 917                let selection_start = snapshot.prev_line_boundary(selection.start).1;
 918                let selection_end = snapshot.next_line_boundary(selection.end).1;
 919                for row in cmp::max(selection_start.row(), start_row)
 920                    ..=cmp::min(selection_end.row(), end_row)
 921                {
 922                    let contains_non_empty_selection = active_rows.entry(row).or_insert(!is_empty);
 923                    *contains_non_empty_selection |= !is_empty;
 924                }
 925            }
 926            selections.insert(
 927                view.replica_id(cx),
 928                local_selections
 929                    .into_iter()
 930                    .map(|selection| crate::Selection {
 931                        id: selection.id,
 932                        goal: selection.goal,
 933                        reversed: selection.reversed,
 934                        start: selection.start.to_display_point(&display_map),
 935                        end: selection.end.to_display_point(&display_map),
 936                    })
 937                    .collect(),
 938            );
 939
 940            for (replica_id, selection) in display_map
 941                .buffer_snapshot
 942                .remote_selections_in_range(&(start_anchor..end_anchor))
 943            {
 944                selections
 945                    .entry(replica_id)
 946                    .or_insert(Vec::new())
 947                    .push(crate::Selection {
 948                        id: selection.id,
 949                        goal: selection.goal,
 950                        reversed: selection.reversed,
 951                        start: selection.start.to_display_point(&display_map),
 952                        end: selection.end.to_display_point(&display_map),
 953                    });
 954            }
 955        });
 956
 957        let line_number_layouts =
 958            self.layout_line_numbers(start_row..end_row, &active_rows, &snapshot, cx);
 959
 960        let mut max_visible_line_width = 0.0;
 961        let line_layouts = self.layout_lines(start_row..end_row, &mut snapshot, cx);
 962        for line in &line_layouts {
 963            if line.width() > max_visible_line_width {
 964                max_visible_line_width = line.width();
 965            }
 966        }
 967
 968        let style = self.style.clone();
 969        let longest_line_width = layout_line(
 970            snapshot.longest_row(),
 971            &snapshot,
 972            &style,
 973            cx.text_layout_cache,
 974        )
 975        .width();
 976        let scroll_width = longest_line_width.max(max_visible_line_width) + overscroll.x();
 977        let em_width = style.text.em_width(cx.font_cache);
 978        let max_row = snapshot.max_point().row();
 979        let scroll_max = vec2f(
 980            ((scroll_width - text_size.x()) / em_width).max(0.0),
 981            max_row.saturating_sub(1) as f32,
 982        );
 983
 984        let mut context_menu = None;
 985        let mut code_actions_indicator = None;
 986        self.update_view(cx.app, |view, cx| {
 987            let clamped = view.clamp_scroll_left(scroll_max.x());
 988            let autoscrolled;
 989            if autoscroll_horizontally {
 990                autoscrolled = view.autoscroll_horizontally(
 991                    start_row,
 992                    text_size.x(),
 993                    scroll_width,
 994                    em_width,
 995                    &line_layouts,
 996                    cx,
 997                );
 998            } else {
 999                autoscrolled = false;
1000            }
1001
1002            if clamped || autoscrolled {
1003                snapshot = view.snapshot(cx);
1004            }
1005
1006            let newest_selection_head = view
1007                .newest_selection_with_snapshot::<usize>(&snapshot.buffer_snapshot)
1008                .head()
1009                .to_display_point(&snapshot);
1010
1011            if (start_row..end_row).contains(&newest_selection_head.row()) {
1012                let style = view.style(cx);
1013                if view.context_menu_visible() {
1014                    context_menu =
1015                        view.render_context_menu(newest_selection_head, style.clone(), cx);
1016                }
1017
1018                code_actions_indicator = view
1019                    .render_code_actions_indicator(&style, cx)
1020                    .map(|indicator| (newest_selection_head.row(), indicator));
1021            }
1022        });
1023
1024        if let Some((_, context_menu)) = context_menu.as_mut() {
1025            context_menu.layout(
1026                SizeConstraint {
1027                    min: Vector2F::zero(),
1028                    max: vec2f(
1029                        f32::INFINITY,
1030                        (12. * line_height).min((size.y() - line_height) / 2.),
1031                    ),
1032                },
1033                cx,
1034            );
1035        }
1036
1037        if let Some((_, indicator)) = code_actions_indicator.as_mut() {
1038            indicator.layout(
1039                SizeConstraint::strict_along(Axis::Vertical, line_height * 0.618),
1040                cx,
1041            );
1042        }
1043
1044        let blocks = self.layout_blocks(
1045            start_row..end_row,
1046            &snapshot,
1047            size.x().max(scroll_width + gutter_width),
1048            gutter_padding,
1049            gutter_width,
1050            em_width,
1051            gutter_width + gutter_margin,
1052            line_height,
1053            &style,
1054            &line_layouts,
1055            cx,
1056        );
1057
1058        (
1059            size,
1060            LayoutState {
1061                size,
1062                scroll_max,
1063                gutter_size,
1064                gutter_padding,
1065                text_size,
1066                gutter_margin,
1067                snapshot,
1068                active_rows,
1069                highlighted_rows,
1070                highlighted_ranges,
1071                line_layouts,
1072                line_number_layouts,
1073                blocks,
1074                line_height,
1075                em_width,
1076                em_advance,
1077                selections,
1078                context_menu,
1079                code_actions_indicator,
1080            },
1081        )
1082    }
1083
1084    fn paint(
1085        &mut self,
1086        bounds: RectF,
1087        visible_bounds: RectF,
1088        layout: &mut Self::LayoutState,
1089        cx: &mut PaintContext,
1090    ) -> Self::PaintState {
1091        cx.scene.push_layer(Some(bounds));
1092
1093        let gutter_bounds = RectF::new(bounds.origin(), layout.gutter_size);
1094        let text_bounds = RectF::new(
1095            bounds.origin() + vec2f(layout.gutter_size.x(), 0.0),
1096            layout.text_size,
1097        );
1098
1099        self.paint_background(gutter_bounds, text_bounds, layout, cx);
1100        if layout.gutter_size.x() > 0. {
1101            self.paint_gutter(gutter_bounds, visible_bounds, layout, cx);
1102        }
1103        self.paint_text(text_bounds, visible_bounds, layout, cx);
1104
1105        if !layout.blocks.is_empty() {
1106            cx.scene.push_layer(Some(bounds));
1107            self.paint_blocks(bounds, visible_bounds, layout, cx);
1108            cx.scene.pop_layer();
1109        }
1110
1111        cx.scene.pop_layer();
1112
1113        PaintState {
1114            bounds,
1115            gutter_bounds,
1116            text_bounds,
1117        }
1118    }
1119
1120    fn dispatch_event(
1121        &mut self,
1122        event: &Event,
1123        _: RectF,
1124        layout: &mut LayoutState,
1125        paint: &mut PaintState,
1126        cx: &mut EventContext,
1127    ) -> bool {
1128        if let Some((_, context_menu)) = &mut layout.context_menu {
1129            if context_menu.dispatch_event(event, cx) {
1130                return true;
1131            }
1132        }
1133
1134        if let Some((_, indicator)) = &mut layout.code_actions_indicator {
1135            if indicator.dispatch_event(event, cx) {
1136                return true;
1137            }
1138        }
1139
1140        for (_, block) in &mut layout.blocks {
1141            if block.dispatch_event(event, cx) {
1142                return true;
1143            }
1144        }
1145
1146        match event {
1147            Event::LeftMouseDown {
1148                position,
1149                alt,
1150                shift,
1151                click_count,
1152                ..
1153            } => self.mouse_down(*position, *alt, *shift, *click_count, layout, paint, cx),
1154            Event::LeftMouseUp { position } => self.mouse_up(*position, cx),
1155            Event::LeftMouseDragged { position } => {
1156                self.mouse_dragged(*position, layout, paint, cx)
1157            }
1158            Event::ScrollWheel {
1159                position,
1160                delta,
1161                precise,
1162            } => self.scroll(*position, *delta, *precise, layout, paint, cx),
1163            Event::KeyDown { input, .. } => self.key_down(input.as_deref(), cx),
1164            _ => false,
1165        }
1166    }
1167
1168    fn debug(
1169        &self,
1170        bounds: RectF,
1171        _: &Self::LayoutState,
1172        _: &Self::PaintState,
1173        _: &gpui::DebugContext,
1174    ) -> json::Value {
1175        json!({
1176            "type": "BufferElement",
1177            "bounds": bounds.to_json()
1178        })
1179    }
1180}
1181
1182pub struct LayoutState {
1183    size: Vector2F,
1184    scroll_max: Vector2F,
1185    gutter_size: Vector2F,
1186    gutter_padding: f32,
1187    gutter_margin: f32,
1188    text_size: Vector2F,
1189    snapshot: EditorSnapshot,
1190    active_rows: BTreeMap<u32, bool>,
1191    highlighted_rows: Option<Range<u32>>,
1192    line_layouts: Vec<text_layout::Line>,
1193    line_number_layouts: Vec<Option<text_layout::Line>>,
1194    blocks: Vec<(u32, ElementBox)>,
1195    line_height: f32,
1196    em_width: f32,
1197    em_advance: f32,
1198    highlighted_ranges: Vec<(Range<DisplayPoint>, Color)>,
1199    selections: HashMap<ReplicaId, Vec<text::Selection<DisplayPoint>>>,
1200    context_menu: Option<(DisplayPoint, ElementBox)>,
1201    code_actions_indicator: Option<(u32, ElementBox)>,
1202}
1203
1204fn layout_line(
1205    row: u32,
1206    snapshot: &EditorSnapshot,
1207    style: &EditorStyle,
1208    layout_cache: &TextLayoutCache,
1209) -> text_layout::Line {
1210    let mut line = snapshot.line(row);
1211
1212    if line.len() > MAX_LINE_LEN {
1213        let mut len = MAX_LINE_LEN;
1214        while !line.is_char_boundary(len) {
1215            len -= 1;
1216        }
1217
1218        line.truncate(len);
1219    }
1220
1221    layout_cache.layout_str(
1222        &line,
1223        style.text.font_size,
1224        &[(
1225            snapshot.line_len(row) as usize,
1226            RunStyle {
1227                font_id: style.text.font_id,
1228                color: Color::black(),
1229                underline: None,
1230            },
1231        )],
1232    )
1233}
1234
1235pub struct PaintState {
1236    bounds: RectF,
1237    gutter_bounds: RectF,
1238    text_bounds: RectF,
1239}
1240
1241impl PaintState {
1242    fn point_for_position(
1243        &self,
1244        snapshot: &EditorSnapshot,
1245        layout: &LayoutState,
1246        position: Vector2F,
1247    ) -> (DisplayPoint, u32) {
1248        let scroll_position = snapshot.scroll_position();
1249        let position = position - self.text_bounds.origin();
1250        let y = position.y().max(0.0).min(layout.size.y());
1251        let row = ((y / layout.line_height) + scroll_position.y()) as u32;
1252        let row = cmp::min(row, snapshot.max_point().row());
1253        let line = &layout.line_layouts[(row - scroll_position.y() as u32) as usize];
1254        let x = position.x() + (scroll_position.x() * layout.em_width);
1255
1256        let column = if x >= 0.0 {
1257            line.index_for_x(x)
1258                .map(|ix| ix as u32)
1259                .unwrap_or_else(|| snapshot.line_len(row))
1260        } else {
1261            0
1262        };
1263        let overshoot = (0f32.max(x - line.width()) / layout.em_advance) as u32;
1264
1265        (DisplayPoint::new(row, column), overshoot)
1266    }
1267}
1268
1269#[derive(Copy, Clone)]
1270pub enum CursorShape {
1271    Bar,
1272    Block,
1273    Underscore,
1274}
1275
1276impl Default for CursorShape {
1277    fn default() -> Self {
1278        CursorShape::Bar
1279    }
1280}
1281
1282struct Cursor {
1283    origin: Vector2F,
1284    block_width: f32,
1285    line_height: f32,
1286    color: Color,
1287    shape: CursorShape,
1288    block_text: Option<Line>,
1289}
1290
1291impl Cursor {
1292    fn paint(&self, cx: &mut PaintContext) {
1293        let bounds = match self.shape {
1294            CursorShape::Bar => RectF::new(self.origin, vec2f(2.0, self.line_height)),
1295            CursorShape::Block => {
1296                RectF::new(self.origin, vec2f(self.block_width, self.line_height))
1297            }
1298            CursorShape::Underscore => RectF::new(
1299                self.origin + Vector2F::new(0.0, self.line_height - 2.0),
1300                vec2f(self.block_width, 2.0),
1301            ),
1302        };
1303
1304        cx.scene.push_quad(Quad {
1305            bounds,
1306            background: Some(self.color),
1307            border: Border::new(0., Color::black()),
1308            corner_radius: 0.,
1309        });
1310
1311        if let Some(block_text) = &self.block_text {
1312            block_text.paint(self.origin, bounds, self.line_height, cx);
1313        }
1314    }
1315}
1316
1317#[derive(Debug)]
1318struct HighlightedRange {
1319    start_y: f32,
1320    line_height: f32,
1321    lines: Vec<HighlightedRangeLine>,
1322    color: Color,
1323    corner_radius: f32,
1324}
1325
1326#[derive(Debug)]
1327struct HighlightedRangeLine {
1328    start_x: f32,
1329    end_x: f32,
1330}
1331
1332impl HighlightedRange {
1333    fn paint(&self, bounds: RectF, scene: &mut Scene) {
1334        if self.lines.len() >= 2 && self.lines[0].start_x > self.lines[1].end_x {
1335            self.paint_lines(self.start_y, &self.lines[0..1], bounds, scene);
1336            self.paint_lines(
1337                self.start_y + self.line_height,
1338                &self.lines[1..],
1339                bounds,
1340                scene,
1341            );
1342        } else {
1343            self.paint_lines(self.start_y, &self.lines, bounds, scene);
1344        }
1345    }
1346
1347    fn paint_lines(
1348        &self,
1349        start_y: f32,
1350        lines: &[HighlightedRangeLine],
1351        bounds: RectF,
1352        scene: &mut Scene,
1353    ) {
1354        if lines.is_empty() {
1355            return;
1356        }
1357
1358        let mut path = PathBuilder::new();
1359        let first_line = lines.first().unwrap();
1360        let last_line = lines.last().unwrap();
1361
1362        let first_top_left = vec2f(first_line.start_x, start_y);
1363        let first_top_right = vec2f(first_line.end_x, start_y);
1364
1365        let curve_height = vec2f(0., self.corner_radius);
1366        let curve_width = |start_x: f32, end_x: f32| {
1367            let max = (end_x - start_x) / 2.;
1368            let width = if max < self.corner_radius {
1369                max
1370            } else {
1371                self.corner_radius
1372            };
1373
1374            vec2f(width, 0.)
1375        };
1376
1377        let top_curve_width = curve_width(first_line.start_x, first_line.end_x);
1378        path.reset(first_top_right - top_curve_width);
1379        path.curve_to(first_top_right + curve_height, first_top_right);
1380
1381        let mut iter = lines.iter().enumerate().peekable();
1382        while let Some((ix, line)) = iter.next() {
1383            let bottom_right = vec2f(line.end_x, start_y + (ix + 1) as f32 * self.line_height);
1384
1385            if let Some((_, next_line)) = iter.peek() {
1386                let next_top_right = vec2f(next_line.end_x, bottom_right.y());
1387
1388                match next_top_right.x().partial_cmp(&bottom_right.x()).unwrap() {
1389                    Ordering::Equal => {
1390                        path.line_to(bottom_right);
1391                    }
1392                    Ordering::Less => {
1393                        let curve_width = curve_width(next_top_right.x(), bottom_right.x());
1394                        path.line_to(bottom_right - curve_height);
1395                        if self.corner_radius > 0. {
1396                            path.curve_to(bottom_right - curve_width, bottom_right);
1397                        }
1398                        path.line_to(next_top_right + curve_width);
1399                        if self.corner_radius > 0. {
1400                            path.curve_to(next_top_right + curve_height, next_top_right);
1401                        }
1402                    }
1403                    Ordering::Greater => {
1404                        let curve_width = curve_width(bottom_right.x(), next_top_right.x());
1405                        path.line_to(bottom_right - curve_height);
1406                        if self.corner_radius > 0. {
1407                            path.curve_to(bottom_right + curve_width, bottom_right);
1408                        }
1409                        path.line_to(next_top_right - curve_width);
1410                        if self.corner_radius > 0. {
1411                            path.curve_to(next_top_right + curve_height, next_top_right);
1412                        }
1413                    }
1414                }
1415            } else {
1416                let curve_width = curve_width(line.start_x, line.end_x);
1417                path.line_to(bottom_right - curve_height);
1418                if self.corner_radius > 0. {
1419                    path.curve_to(bottom_right - curve_width, bottom_right);
1420                }
1421
1422                let bottom_left = vec2f(line.start_x, bottom_right.y());
1423                path.line_to(bottom_left + curve_width);
1424                if self.corner_radius > 0. {
1425                    path.curve_to(bottom_left - curve_height, bottom_left);
1426                }
1427            }
1428        }
1429
1430        if first_line.start_x > last_line.start_x {
1431            let curve_width = curve_width(last_line.start_x, first_line.start_x);
1432            let second_top_left = vec2f(last_line.start_x, start_y + self.line_height);
1433            path.line_to(second_top_left + curve_height);
1434            if self.corner_radius > 0. {
1435                path.curve_to(second_top_left + curve_width, second_top_left);
1436            }
1437            let first_bottom_left = vec2f(first_line.start_x, second_top_left.y());
1438            path.line_to(first_bottom_left - curve_width);
1439            if self.corner_radius > 0. {
1440                path.curve_to(first_bottom_left - curve_height, first_bottom_left);
1441            }
1442        }
1443
1444        path.line_to(first_top_left + curve_height);
1445        if self.corner_radius > 0. {
1446            path.curve_to(first_top_left + top_curve_width, first_top_left);
1447        }
1448        path.line_to(first_top_right - top_curve_width);
1449
1450        scene.push_path(path.build(self.color, Some(bounds)));
1451    }
1452}
1453
1454fn scale_vertical_mouse_autoscroll_delta(delta: f32) -> f32 {
1455    delta.powf(1.5) / 100.0
1456}
1457
1458fn scale_horizontal_mouse_autoscroll_delta(delta: f32) -> f32 {
1459    delta.powf(1.2) / 300.0
1460}
1461
1462#[cfg(test)]
1463mod tests {
1464    use super::*;
1465    use crate::{Editor, MultiBuffer};
1466    use postage::watch;
1467    use util::test::sample_text;
1468    use workspace::Settings;
1469
1470    #[gpui::test]
1471    fn test_layout_line_numbers(cx: &mut gpui::MutableAppContext) {
1472        let settings = watch::channel_with(Settings::test(cx));
1473        let buffer = MultiBuffer::build_simple(&sample_text(6, 6, 'a'), cx);
1474        let (window_id, editor) = cx.add_window(Default::default(), |cx| {
1475            Editor::new(EditorMode::Full, buffer, None, settings.1, None, cx)
1476        });
1477        let element = EditorElement::new(editor.downgrade(), editor.read(cx).style(cx), CursorShape::Bar);
1478
1479        let layouts = editor.update(cx, |editor, cx| {
1480            let snapshot = editor.snapshot(cx);
1481            let mut presenter = cx.build_presenter(window_id, 30.);
1482            let mut layout_cx = presenter.build_layout_context(false, cx);
1483            element.layout_line_numbers(0..6, &Default::default(), &snapshot, &mut layout_cx)
1484        });
1485        assert_eq!(layouts.len(), 6);
1486    }
1487}