Add interactable fold markers

Mikayla Maki and Max created

Change fold handlers to be driven by the fold map
Switch to a mouse region based implementation for click regions

Co-authored-by: Max <max@zed.dev>

Change summary

crates/editor/src/display_map.rs          |  5 +
crates/editor/src/display_map/fold_map.rs | 25 +++++++
crates/editor/src/editor.rs               |  6 
crates/editor/src/element.rs              | 82 +++++++++++++++++-------
crates/gpui/src/app.rs                    |  8 +-
crates/gpui/src/presenter.rs              | 24 ++++++
crates/theme/src/theme.rs                 | 16 +++-
styles/src/styleTree/editor.ts            | 16 ++++
8 files changed, 140 insertions(+), 42 deletions(-)

Detailed changes

crates/editor/src/display_map.rs 🔗

@@ -8,6 +8,7 @@ use block_map::{BlockMap, BlockPoint};
 use collections::{HashMap, HashSet};
 use fold_map::FoldMap;
 use gpui::{
+    color::Color,
     fonts::{FontId, HighlightStyle},
     Entity, ModelContext, ModelHandle,
 };
@@ -218,6 +219,10 @@ impl DisplayMap {
             .update(cx, |map, cx| map.set_font(font_id, font_size, cx))
     }
 
+    pub fn set_fold_ellipses_color(&mut self, color: Color) -> bool {
+        self.fold_map.set_ellipses_color(color)
+    }
+
     pub fn set_wrap_width(&self, width: Option<f32>, cx: &mut ModelContext<Self>) -> bool {
         self.wrap_map
             .update(cx, |map, cx| map.set_wrap_width(width, cx))

crates/editor/src/display_map/fold_map.rs 🔗

@@ -4,7 +4,7 @@ use crate::{
     ToOffset,
 };
 use collections::BTreeMap;
-use gpui::fonts::HighlightStyle;
+use gpui::{color::Color, fonts::HighlightStyle};
 use language::{Chunk, Edit, Point, TextSummary};
 use parking_lot::Mutex;
 use std::{
@@ -133,6 +133,7 @@ impl<'a> FoldMapWriter<'a> {
             folds: self.0.folds.clone(),
             buffer_snapshot: buffer,
             version: self.0.version.load(SeqCst),
+            ellipses_color: self.0.ellipses_color,
         };
         (snapshot, edits)
     }
@@ -182,6 +183,7 @@ impl<'a> FoldMapWriter<'a> {
             folds: self.0.folds.clone(),
             buffer_snapshot: buffer,
             version: self.0.version.load(SeqCst),
+            ellipses_color: self.0.ellipses_color,
         };
         (snapshot, edits)
     }
@@ -192,6 +194,7 @@ pub struct FoldMap {
     transforms: Mutex<SumTree<Transform>>,
     folds: SumTree<Fold>,
     version: AtomicUsize,
+    ellipses_color: Option<Color>,
 }
 
 impl FoldMap {
@@ -209,6 +212,7 @@ impl FoldMap {
                 },
                 &(),
             )),
+            ellipses_color: None,
             version: Default::default(),
         };
 
@@ -217,6 +221,7 @@ impl FoldMap {
             folds: this.folds.clone(),
             buffer_snapshot: this.buffer.lock().clone(),
             version: this.version.load(SeqCst),
+            ellipses_color: None,
         };
         (this, snapshot)
     }
@@ -233,6 +238,7 @@ impl FoldMap {
             folds: self.folds.clone(),
             buffer_snapshot: self.buffer.lock().clone(),
             version: self.version.load(SeqCst),
+            ellipses_color: self.ellipses_color,
         };
         (snapshot, edits)
     }
@@ -246,6 +252,15 @@ impl FoldMap {
         (FoldMapWriter(self), snapshot, edits)
     }
 
+    pub fn set_ellipses_color(&mut self, color: Color) -> bool {
+        if self.ellipses_color != Some(color) {
+            self.ellipses_color = Some(color);
+            true
+        } else {
+            false
+        }
+    }
+
     fn check_invariants(&self) {
         if cfg!(test) {
             assert_eq!(
@@ -477,6 +492,7 @@ pub struct FoldSnapshot {
     folds: SumTree<Fold>,
     buffer_snapshot: MultiBufferSnapshot,
     pub version: usize,
+    pub ellipses_color: Option<Color>,
 }
 
 impl FoldSnapshot {
@@ -739,6 +755,7 @@ impl FoldSnapshot {
             max_output_offset: range.end.0,
             highlight_endpoints: highlight_endpoints.into_iter().peekable(),
             active_highlights: Default::default(),
+            ellipses_color: self.ellipses_color,
         }
     }
 
@@ -1029,6 +1046,7 @@ pub struct FoldChunks<'a> {
     max_output_offset: usize,
     highlight_endpoints: Peekable<vec::IntoIter<HighlightEndpoint>>,
     active_highlights: BTreeMap<Option<TypeId>, HighlightStyle>,
+    ellipses_color: Option<Color>,
 }
 
 impl<'a> Iterator for FoldChunks<'a> {
@@ -1058,7 +1076,10 @@ impl<'a> Iterator for FoldChunks<'a> {
             return Some(Chunk {
                 text: output_text,
                 syntax_highlight_id: None,
-                highlight_style: None,
+                highlight_style: self.ellipses_color.map(|color| HighlightStyle {
+                    color: Some(color),
+                    ..Default::default()
+                }),
                 diagnostic_severity: None,
                 is_unnecessary: false,
             });

crates/editor/src/editor.rs 🔗

@@ -39,11 +39,10 @@ use gpui::{
     impl_actions, impl_internal_actions,
     keymap_matcher::KeymapContext,
     platform::CursorStyle,
-    scene::MouseClick,
     serde_json::json,
     AnyViewHandle, AppContext, AsyncAppContext, ClipboardItem, Element, ElementBox, Entity,
-    EventContext, ModelHandle, MouseButton, MutableAppContext, RenderContext, Subscription, Task,
-    View, ViewContext, ViewHandle, WeakViewHandle,
+    ModelHandle, MouseButton, MutableAppContext, RenderContext, Subscription, Task, View,
+    ViewContext, ViewHandle, WeakViewHandle,
 };
 use highlight_matching_bracket::refresh_matching_bracket_highlights;
 use hover_popover::{hide_hover, HideHover, HoverState};
@@ -6448,6 +6447,7 @@ impl View for Editor {
     fn render(&mut self, cx: &mut RenderContext<Self>) -> ElementBox {
         let style = self.style(cx);
         let font_changed = self.display_map.update(cx, |map, cx| {
+            map.set_fold_ellipses_color(style.folds.ellipses.text_color);
             map.set_font(style.text.font_id, style.text.font_size, cx)
         });
 

crates/editor/src/element.rs 🔗

@@ -50,6 +50,8 @@ use std::{
 };
 use workspace::item::Item;
 
+enum FoldMarkers {}
+
 struct SelectionLayout {
     head: DisplayPoint,
     cursor_shape: CursorShape,
@@ -115,7 +117,6 @@ impl EditorElement {
     fn attach_mouse_handlers(
         view: &WeakViewHandle<Editor>,
         position_map: &Arc<PositionMap>,
-        fold_ranges: Arc<[Range<DisplayPoint>]>,
         has_popovers: bool,
         visible_bounds: RectF,
         text_bounds: RectF,
@@ -212,23 +213,6 @@ impl EditorElement {
                             cx.propagate_event()
                         }
                     }
-                })
-                .on_click(MouseButton::Left, {
-                    let position_map = position_map.clone();
-                    move |e, cx| {
-                        let point =
-                            position_to_display_point(e.position, text_bounds, &position_map);
-                        if let Some(point) = point {
-                            for range in fold_ranges.iter() {
-                                // Range -> RangeInclusive
-                                if range.contains(&point) || range.end == point {
-                                    cx.dispatch_action(UnfoldAt {
-                                        display_row: point.row(),
-                                    })
-                                }
-                            }
-                        }
-                    }
                 }),
         );
 
@@ -724,9 +708,24 @@ impl EditorElement {
             },
         });
 
-        for range in layout.fold_ranges.iter() {
+        let fold_corner_radius =
+            self.style.folds.ellipses.corner_radius_factor * layout.position_map.line_height;
+        for (id, range, color) in layout.fold_ranges.iter() {
+            self.paint_highlighted_range(
+                range.clone(),
+                *color,
+                fold_corner_radius,
+                fold_corner_radius * 2.,
+                layout,
+                content_origin,
+                scroll_top,
+                scroll_left,
+                bounds,
+                cx,
+            );
+
             for bound in range_to_bounds(
-                range,
+                &range,
                 content_origin,
                 scroll_left,
                 scroll_top,
@@ -738,6 +737,16 @@ impl EditorElement {
                     bounds: bound,
                     style: CursorStyle::PointingHand,
                 });
+
+                let display_row = range.start.row();
+                cx.scene.push_mouse_region(
+                    MouseRegion::new::<FoldMarkers>(self.view.id(), *id as usize, bound)
+                        .on_click(MouseButton::Left, move |_, cx| {
+                            cx.dispatch_action(UnfoldAt { display_row })
+                        })
+                        .with_notify_on_hover(true)
+                        .with_notify_on_click(true),
+                )
             }
         }
 
@@ -757,9 +766,10 @@ impl EditorElement {
         }
 
         let mut cursors = SmallVec::<[Cursor; 32]>::new();
+        let corner_radius = 0.15 * layout.position_map.line_height;
+
         for (replica_id, selections) in &layout.selections {
             let selection_style = style.replica_selection_style(*replica_id);
-            let corner_radius = 0.15 * layout.position_map.line_height;
 
             for selection in selections {
                 self.paint_highlighted_range(
@@ -1695,8 +1705,12 @@ impl Element for EditorElement {
                 snapshot
                     .folds_in_range(start_anchor..end_anchor)
                     .map(|anchor| {
-                        anchor.start.to_display_point(&snapshot.display_snapshot)
-                            ..anchor.end.to_display_point(&snapshot.display_snapshot)
+                        let start = anchor.start.to_point(&snapshot.buffer_snapshot);
+                        (
+                            start.row,
+                            start.to_display_point(&snapshot.display_snapshot)
+                                ..anchor.end.to_display_point(&snapshot),
+                        )
                     }),
             );
 
@@ -1768,6 +1782,21 @@ impl Element for EditorElement {
                 .unwrap_or_default()
         });
 
+        let fold_ranges: Vec<(BufferRow, Range<DisplayPoint>, Color)> = fold_ranges
+            .into_iter()
+            .map(|(id, fold)| {
+                let color = self
+                    .style
+                    .folds
+                    .ellipses
+                    .background
+                    .style_for(&mut cx.mouse_state::<FoldMarkers>(id as usize), false)
+                    .color;
+
+                (id, fold, color)
+            })
+            .collect();
+
         let line_number_layouts =
             self.layout_line_numbers(start_row..end_row, &active_rows, &snapshot, cx);
 
@@ -1955,7 +1984,7 @@ impl Element for EditorElement {
                 active_rows,
                 highlighted_rows,
                 highlighted_ranges,
-                fold_ranges: fold_ranges.into(),
+                fold_ranges,
                 line_number_layouts,
                 display_hunks,
                 blocks,
@@ -1987,7 +2016,6 @@ impl Element for EditorElement {
         Self::attach_mouse_handlers(
             &self.view,
             &layout.position_map,
-            layout.fold_ranges.clone(), // No need to clone the vec
             layout.hover_popovers.is_some(),
             visible_bounds,
             text_bounds,
@@ -2071,6 +2099,8 @@ impl Element for EditorElement {
     }
 }
 
+type BufferRow = u32;
+
 pub struct LayoutState {
     position_map: Arc<PositionMap>,
     gutter_size: Vector2F,
@@ -2085,7 +2115,7 @@ pub struct LayoutState {
     display_hunks: Vec<DisplayDiffHunk>,
     blocks: Vec<BlockLayout>,
     highlighted_ranges: Vec<(Range<DisplayPoint>, Color)>,
-    fold_ranges: Arc<[Range<DisplayPoint>]>,
+    fold_ranges: Vec<(BufferRow, Range<DisplayPoint>, Color)>,
     selections: Vec<(ReplicaId, Vec<SelectionLayout>)>,
     scrollbar_row_range: Range<f32>,
     show_scrollbars: bool,

crates/gpui/src/app.rs 🔗

@@ -4159,10 +4159,10 @@ pub struct RenderContext<'a, T: View> {
 
 #[derive(Debug, Clone, Default)]
 pub struct MouseState {
-    hovered: bool,
-    clicked: Option<MouseButton>,
-    accessed_hovered: bool,
-    accessed_clicked: bool,
+    pub(crate) hovered: bool,
+    pub(crate) clicked: Option<MouseButton>,
+    pub(crate) accessed_hovered: bool,
+    pub(crate) accessed_clicked: bool,
 }
 
 impl MouseState {

crates/gpui/src/presenter.rs 🔗

@@ -12,9 +12,9 @@ use crate::{
     text_layout::TextLayoutCache,
     Action, AnyModelHandle, AnyViewHandle, AnyWeakModelHandle, AnyWeakViewHandle, Appearance,
     AssetCache, ElementBox, Entity, FontSystem, ModelHandle, MouseButton, MouseMovedEvent,
-    MouseRegion, MouseRegionId, ParentId, ReadModel, ReadView, RenderContext, RenderParams,
-    SceneBuilder, UpgradeModelHandle, UpgradeViewHandle, View, ViewHandle, WeakModelHandle,
-    WeakViewHandle,
+    MouseRegion, MouseRegionId, MouseState, ParentId, ReadModel, ReadView, RenderContext,
+    RenderParams, SceneBuilder, UpgradeModelHandle, UpgradeViewHandle, View, ViewHandle,
+    WeakModelHandle, WeakViewHandle,
 };
 use anyhow::bail;
 use collections::{HashMap, HashSet};
@@ -603,6 +603,24 @@ pub struct LayoutContext<'a> {
 }
 
 impl<'a> LayoutContext<'a> {
+    pub fn mouse_state<Tag: 'static>(&self, region_id: usize) -> MouseState {
+        let view_id = self.view_stack.last().unwrap();
+
+        let region_id = MouseRegionId::new::<Tag>(*view_id, region_id);
+        MouseState {
+            hovered: self.hovered_region_ids.contains(&region_id),
+            clicked: self.clicked_region_ids.as_ref().and_then(|(ids, button)| {
+                if ids.contains(&region_id) {
+                    Some(*button)
+                } else {
+                    None
+                }
+            }),
+            accessed_hovered: false,
+            accessed_clicked: false,
+        }
+    }
+
     fn layout(&mut self, view_id: usize, constraint: SizeConstraint) -> Vector2F {
         let print_error = |view_id| {
             format!(

crates/theme/src/theme.rs 🔗

@@ -632,16 +632,22 @@ pub struct FieldEditor {
     pub selection: SelectionStyle,
 }
 
+#[derive(Clone, Deserialize, Default)]
+pub struct InteractiveColor {
+    pub color: Color,
+}
+
 #[derive(Clone, Deserialize, Default)]
 pub struct CodeActions {
     #[serde(default)]
-    pub indicator: Interactive<Indicator>,
+    pub indicator: Interactive<InteractiveColor>,
     pub vertical_scale: f32,
 }
 
 #[derive(Clone, Deserialize, Default)]
 pub struct Folds {
-    pub indicator: Interactive<Indicator>,
+    pub indicator: Interactive<InteractiveColor>,
+    pub ellipses: FoldEllipses,
     pub fold_background: Color,
     pub icon_width: f32,
     pub folded_icon: String,
@@ -649,8 +655,10 @@ pub struct Folds {
 }
 
 #[derive(Clone, Deserialize, Default)]
-pub struct Indicator {
-    pub color: Color,
+pub struct FoldEllipses {
+    pub text_color: Color,
+    pub background: Interactive<InteractiveColor>,
+    pub corner_radius_factor: f32,
 }
 
 #[derive(Clone, Deserialize, Default)]

styles/src/styleTree/editor.ts 🔗

@@ -76,6 +76,22 @@ export default function editor(colorScheme: ColorScheme) {
                     color: foreground(layer, "on"),
                 },
             },
+            ellipses: {
+                textColor: colorScheme.ramps.neutral(0.71).hex(),
+                cornerRadiusFactor: 0.15,
+                background: {
+                    // Copied from hover_popover highlight
+                    color: colorScheme.ramps.neutral(0.5).alpha(0.0).hex(),
+
+                    hover: {
+                        color: colorScheme.ramps.neutral(0.5).alpha(0.5).hex(),
+                    },
+
+                    clicked: {
+                        color: colorScheme.ramps.neutral(0.5).alpha(0.7).hex(),
+                    },
+                }
+            },
             foldBackground: foreground(layer, "variant"),
         },
         diff: {