Overhaul inline assistant (#12846)

This pull request introduces a new diff mechanism that helps users
understand exactly which lines were changed by the LLM.

Release Notes:

- N/A

crates/assistant/Cargo.toml

@@ -47,6 +47,7 @@ semantic_index.workspace = true
 serde.workspace = true
 serde_json.workspace = true
 settings.workspace = true
+similar.workspace = true
 smol.workspace = true
 strsim = "0.11"
 strum.workspace = true

crates/assistant/src/assistant_panel.rs

@@ -1222,6 +1222,10 @@ impl Context {
         }
     }
 
+    pub(crate) fn token_count(&self) -> Option<usize> {
+        self.token_count
+    }
+
     pub(crate) fn count_remaining_tokens(&mut self, cx: &mut ModelContext<Self>) {
         let request = self.to_completion_request(cx);
         self.pending_token_count = cx.spawn(|this, mut cx| {

crates/editor/src/display_map.rs

@@ -52,8 +52,14 @@ use multi_buffer::{
     ToOffset, ToPoint,
 };
 use serde::Deserialize;
-use std::ops::Add;
-use std::{any::TypeId, borrow::Cow, fmt::Debug, num::NonZeroU32, ops::Range, sync::Arc};
+use std::{
+    any::TypeId,
+    borrow::Cow,
+    fmt::Debug,
+    num::NonZeroU32,
+    ops::{Add, Range, Sub},
+    sync::Arc,
+};
 use sum_tree::{Bias, TreeMap};
 use tab_map::{TabMap, TabSnapshot};
 use text::LineIndent;
@@ -1027,6 +1033,14 @@ impl Add for DisplayRow {
     }
 }
 
+impl Sub for DisplayRow {
+    type Output = Self;
+
+    fn sub(self, other: Self) -> Self::Output {
+        DisplayRow(self.0 - other.0)
+    }
+}
+
 impl DisplayPoint {
     pub fn new(row: DisplayRow, column: u32) -> Self {
         Self(BlockPoint(Point::new(row.0, column)))

crates/editor/src/editor.rs

@@ -376,6 +376,7 @@ type CompletionId = usize;
 // type OverrideTextStyle = dyn Fn(&EditorStyle) -> Option<HighlightStyle>;
 
 type BackgroundHighlight = (fn(&ThemeColors) -> Hsla, Arc<[Range<Anchor>]>);
+type GutterHighlight = (fn(&AppContext) -> Hsla, Arc<[Range<Anchor>]>);
 
 struct ScrollbarMarkerState {
     scrollbar_size: Size<Pixels>,
@@ -464,6 +465,7 @@ pub struct Editor {
     highlight_order: usize,
     highlighted_rows: HashMap<TypeId, Vec<RowHighlight>>,
     background_highlights: TreeMap<TypeId, BackgroundHighlight>,
+    gutter_highlights: TreeMap<TypeId, GutterHighlight>,
     scrollbar_marker_state: ScrollbarMarkerState,
     active_indent_guides_state: ActiveIndentGuidesState,
     nav_history: Option<ItemNavHistory>,
@@ -1752,6 +1754,7 @@ impl Editor {
             highlight_order: 0,
             highlighted_rows: HashMap::default(),
             background_highlights: Default::default(),
+            gutter_highlights: TreeMap::default(),
             scrollbar_marker_state: ScrollbarMarkerState::default(),
             active_indent_guides_state: ActiveIndentGuidesState::default(),
             nav_history: None,
@@ -10263,6 +10266,25 @@ impl Editor {
         Some(text_highlights)
     }
 
+    pub fn highlight_gutter<T: 'static>(
+        &mut self,
+        ranges: &[Range<Anchor>],
+        color_fetcher: fn(&AppContext) -> Hsla,
+        cx: &mut ViewContext<Self>,
+    ) {
+        self.gutter_highlights
+            .insert(TypeId::of::<T>(), (color_fetcher, Arc::from(ranges)));
+        cx.notify();
+    }
+
+    pub fn clear_gutter_highlights<T: 'static>(
+        &mut self,
+        cx: &mut ViewContext<Self>,
+    ) -> Option<GutterHighlight> {
+        cx.notify();
+        self.gutter_highlights.remove(&TypeId::of::<T>())
+    }
+
     #[cfg(feature = "test-support")]
     pub fn all_text_background_highlights(
         &mut self,
@@ -10452,6 +10474,44 @@ impl Editor {
         results
     }
 
+    pub fn gutter_highlights_in_range(
+        &self,
+        search_range: Range<Anchor>,
+        display_snapshot: &DisplaySnapshot,
+        cx: &AppContext,
+    ) -> Vec<(Range<DisplayPoint>, Hsla)> {
+        let mut results = Vec::new();
+        for (color_fetcher, ranges) in self.gutter_highlights.values() {
+            let color = color_fetcher(cx);
+            let start_ix = match ranges.binary_search_by(|probe| {
+                let cmp = probe
+                    .end
+                    .cmp(&search_range.start, &display_snapshot.buffer_snapshot);
+                if cmp.is_gt() {
+                    Ordering::Greater
+                } else {
+                    Ordering::Less
+                }
+            }) {
+                Ok(i) | Err(i) => i,
+            };
+            for range in &ranges[start_ix..] {
+                if range
+                    .start
+                    .cmp(&search_range.end, &display_snapshot.buffer_snapshot)
+                    .is_ge()
+                {
+                    break;
+                }
+
+                let start = range.start.to_display_point(&display_snapshot);
+                let end = range.end.to_display_point(&display_snapshot);
+                results.push((start..end, color))
+            }
+        }
+        results
+    }
+
     /// Get the text ranges corresponding to the redaction query
     pub fn redacted_ranges(
         &self,

crates/editor/src/element.rs

@@ -2837,6 +2837,8 @@ impl EditorElement {
             Self::paint_diff_hunks(layout.gutter_hitbox.bounds, layout, cx)
         }
 
+        self.paint_gutter_highlights(layout, cx);
+
         if layout.blamed_display_rows.is_some() {
             self.paint_blamed_display_rows(layout, cx);
         }
@@ -3006,6 +3008,37 @@ impl EditorElement {
         }
     }
 
+    fn paint_gutter_highlights(&self, layout: &EditorLayout, cx: &mut WindowContext) {
+        let highlight_width = 0.275 * layout.position_map.line_height;
+        let highlight_corner_radii = Corners::all(0.05 * layout.position_map.line_height);
+        cx.paint_layer(layout.gutter_hitbox.bounds, |cx| {
+            for (range, color) in &layout.highlighted_gutter_ranges {
+                let start_row = if range.start.row() < layout.visible_display_row_range.start {
+                    layout.visible_display_row_range.start - DisplayRow(1)
+                } else {
+                    range.start.row()
+                };
+                let end_row = if range.end.row() > layout.visible_display_row_range.end {
+                    layout.visible_display_row_range.end + DisplayRow(1)
+                } else {
+                    range.end.row()
+                };
+
+                let start_y = layout.gutter_hitbox.top()
+                    + start_row.0 as f32 * layout.position_map.line_height
+                    - layout.position_map.scroll_pixel_position.y;
+                let end_y = layout.gutter_hitbox.top()
+                    + (end_row.0 + 1) as f32 * layout.position_map.line_height
+                    - layout.position_map.scroll_pixel_position.y;
+                let bounds = Bounds::from_corners(
+                    point(layout.gutter_hitbox.left(), start_y),
+                    point(layout.gutter_hitbox.left() + highlight_width, end_y),
+                );
+                cx.paint_quad(fill(bounds, *color).corner_radii(highlight_corner_radii));
+            }
+        });
+    }
+
     fn paint_blamed_display_rows(&self, layout: &mut EditorLayout, cx: &mut WindowContext) {
         let Some(blamed_display_rows) = layout.blamed_display_rows.take() else {
             return;
@@ -4631,6 +4664,12 @@ impl Element for EditorElement {
                         &snapshot.display_snapshot,
                         cx.theme().colors(),
                     );
+                    let highlighted_gutter_ranges =
+                        self.editor.read(cx).gutter_highlights_in_range(
+                            start_anchor..end_anchor,
+                            &snapshot.display_snapshot,
+                            cx,
+                        );
 
                     let redacted_ranges = self.editor.read(cx).redacted_ranges(
                         start_anchor..end_anchor,
@@ -4991,6 +5030,7 @@ impl Element for EditorElement {
                         active_rows,
                         highlighted_rows,
                         highlighted_ranges,
+                        highlighted_gutter_ranges,
                         redacted_ranges,
                         line_elements,
                         line_numbers,
@@ -5121,6 +5161,7 @@ pub struct EditorLayout {
     inline_blame: Option<AnyElement>,
     blocks: Vec<BlockLayout>,
     highlighted_ranges: Vec<(Range<DisplayPoint>, Hsla)>,
+    highlighted_gutter_ranges: Vec<(Range<DisplayPoint>, Hsla)>,
     redacted_ranges: Vec<Range<DisplayPoint>>,
     cursors: Vec<(DisplayPoint, Hsla)>,
     visible_cursors: Vec<CursorLayout>,

crates/language/Cargo.toml

@@ -49,7 +49,7 @@ schemars.workspace = true
 serde.workspace = true
 serde_json.workspace = true
 settings.workspace = true
-similar = "1.3"
+similar.workspace = true
 smallvec.workspace = true
 smol.workspace = true
 sum_tree.workspace = true

crates/language/src/buffer.rs

@@ -797,6 +797,10 @@ impl Buffer {
             .set_language_registry(language_registry);
     }
 
+    pub fn language_registry(&self) -> Option<Arc<LanguageRegistry>> {
+        self.syntax_map.lock().language_registry()
+    }
+
     /// Assign the buffer a new [Capability].
     pub fn set_capability(&mut self, capability: Capability, cx: &mut ModelContext<Self>) {
         self.capability = capability;

crates/ui/src/components/icon.rs

@@ -106,6 +106,7 @@ pub enum IconName {
     Code,
     Collab,
     Command,
+    Context,
     Control,
     Copilot,
     CopilotDisabled,
@@ -170,6 +171,7 @@ pub enum IconName {
     Rerun,
     Return,
     Reveal,
+    RotateCw,
     Save,
     Screen,
     SelectAll,
@@ -186,6 +188,7 @@ pub enum IconName {
     Split,
     Star,
     StarFilled,
+    Stop,
     Strikethrough,
     Supermaven,
     SupermavenDisabled,
@@ -233,6 +236,7 @@ impl IconName {
             IconName::Code => "icons/code.svg",
             IconName::Collab => "icons/user_group_16.svg",
             IconName::Command => "icons/command.svg",
+            IconName::Context => "icons/context.svg",
             IconName::Control => "icons/control.svg",
             IconName::Copilot => "icons/copilot.svg",
             IconName::CopilotDisabled => "icons/copilot_disabled.svg",
@@ -297,6 +301,7 @@ impl IconName {
             IconName::ReplyArrowRight => "icons/reply_arrow_right.svg",
             IconName::Rerun => "icons/rerun.svg",
             IconName::Return => "icons/return.svg",
+            IconName::RotateCw => "icons/rotate_cw.svg",
             IconName::Save => "icons/save.svg",
             IconName::Screen => "icons/desktop.svg",
             IconName::SelectAll => "icons/select_all.svg",
@@ -313,6 +318,7 @@ impl IconName {
             IconName::Split => "icons/split.svg",
             IconName::Star => "icons/star.svg",
             IconName::StarFilled => "icons/star_filled.svg",
+            IconName::Stop => "icons/stop.svg",
             IconName::Strikethrough => "icons/strikethrough.svg",
             IconName::Supermaven => "icons/supermaven.svg",
             IconName::SupermavenDisabled => "icons/supermaven_disabled.svg",