input: gutter markers, range decorations, and inline widgets

Editors can now show feature-owned markers in a reserved gutter lane,
geometric Fill/Frame decorations over UTF-8 ranges, and non-document
inline widgets at an offset. All three follow text edits and are exposed
through InputBaseState setters plus an Editor builder for the marker
renderer; markers report clicks through InputEvent::GutterMarkerMouseDown.

Co-Authored-By: Claude <noreply@anthropic.com>

Author: feigeCode

crates/base/src/input/base/element.rs

@@ -21,15 +21,17 @@
 //! reachable.
 
 use std::cell::RefCell;
+use std::collections::HashMap;
 use std::rc::Rc;
 
-use gpui::{Div, Entity, Stateful, Window};
+use gpui::{Bounds, Div, Entity, Pixels, SharedString, Stateful, Window};
 use ropey::Rope;
 
-use super::decorations::DecorationCollections;
+use super::decorations::{DecorationCollections, EditorAnnotations};
 use super::lsp::{ContextMenuContent, HoverDefinition, InlineCompletion};
 use crate::input::{
-    HighlightStyleResolver, InputEdit, InputHighlighter, SyntaxContext, TextDecoration,
+    GutterMarker, HighlightStyleResolver, InlineWidget, InputEdit, InputHighlighter,
+    RangeDecoration, SyntaxContext, TextDecoration,
 };
 use crate::input::{HoverPopoverState, Lsp};
 use gpui::Task;
@@ -115,6 +117,36 @@ pub trait InputExtras: Default + 'static {
     fn context_menu_capabilities(&self) -> (bool, bool) {
         (false, false)
     }
+
+    /// Feature-owned gutter markers anchored to logical rows.
+    fn gutter_markers(&self) -> &[GutterMarker] {
+        &[]
+    }
+
+    /// Whether the gutter marker lane has ever been used and stays reserved.
+    fn gutter_lane_reserved(&self) -> bool {
+        false
+    }
+
+    /// The application-owned presentation for gutter markers, if any.
+    fn gutter_marker_renderer(&self) -> Option<crate::input::GutterMarkerRenderer> {
+        None
+    }
+
+    /// Last-paint bounds per gutter marker, keyed by marker id.
+    fn gutter_marker_bounds(&self) -> Option<Rc<RefCell<HashMap<SharedString, Bounds<Pixels>>>>> {
+        None
+    }
+
+    /// Geometric range decorations to paint.
+    fn range_decorations(&self) -> &[RangeDecoration] {
+        &[]
+    }
+
+    /// Non-document inline widgets to paint at their offsets.
+    fn inline_widgets(&self) -> &[InlineWidget] {
+        &[]
+    }
 }
 
 /// A mode with nothing extra to render.
@@ -341,6 +373,7 @@ pub struct EditorExtras {
     pub(crate) hover_popover: Option<HoverPopoverState>,
     pub(crate) hover_definition: HoverDefinition,
     pub(crate) context_menu_task: Task<anyhow::Result<()>>,
+    pub(crate) annotations: EditorAnnotations,
 }
 
 impl Default for EditorExtras {
@@ -353,6 +386,7 @@ impl Default for EditorExtras {
             hover_popover: None,
             hover_definition: HoverDefinition::default(),
             context_menu_task: Task::ready(Ok(())),
+            annotations: EditorAnnotations::default(),
         }
     }
 }

crates/base/src/input/base/kind.rs

@@ -121,9 +121,16 @@ actions!(
 #[derive(Clone)]
 pub enum InputEvent {
     Change,
-    PressEnter { secondary: bool, shift: bool },
+    PressEnter {
+        secondary: bool,
+        shift: bool,
+    },
     Focus,
     Blur,
+    GutterMarkerMouseDown {
+        marker_id: SharedString,
+        logical_row: usize,
+    },
 }
 
 pub(super) const CONTEXT: &str = "Input";