Add a live Rust style editor to inspector to edit a sequence of no-argument style modifiers (#31443)

Editing JSON styles is not very helpful for bringing style changes back
to the actual code. This PR adds a buffer that pretends to be Rust,
applying any style attribute identifiers it finds. Also supports
completions with display of documentation. The effect of the currently
selected completion is previewed. Warning diagnostics appear on any
unrecognized identifier.


https://github.com/user-attachments/assets/af39ff0a-26a5-4835-a052-d8f642b2080c

Adds a `#[derive_inspector_reflection]` macro which allows these methods
to be enumerated and called by their name. The macro code changes were
95% generated by Zed Agent + Opus 4.

Release Notes:

* Added an element inspector for development. On debug builds,
`dev::ToggleInspector` will open a pane allowing inspecting of element
info and modifying styles.

crates/editor/src/editor.rs

@@ -77,7 +77,7 @@ use futures::{
     FutureExt,
     future::{self, Shared, join},
 };
-use fuzzy::StringMatchCandidate;
+use fuzzy::{StringMatch, StringMatchCandidate};
 
 use ::git::blame::BlameEntry;
 use ::git::{Restore, blame::ParsedCommitMessage};
@@ -912,7 +912,7 @@ pub struct Editor {
     // TODO: make this a access method
     pub project: Option<Entity<Project>>,
     semantics_provider: Option<Rc<dyn SemanticsProvider>>,
-    completion_provider: Option<Box<dyn CompletionProvider>>,
+    completion_provider: Option<Rc<dyn CompletionProvider>>,
     collaboration_hub: Option<Box<dyn CollaborationHub>>,
     blink_manager: Entity<BlinkManager>,
     show_cursor_names: bool,
@@ -1755,7 +1755,7 @@ impl Editor {
             soft_wrap_mode_override,
             diagnostics_max_severity,
             hard_wrap: None,
-            completion_provider: project.clone().map(|project| Box::new(project) as _),
+            completion_provider: project.clone().map(|project| Rc::new(project) as _),
             semantics_provider: project.clone().map(|project| Rc::new(project) as _),
             collaboration_hub: project.clone().map(|project| Box::new(project) as _),
             project,
@@ -2374,7 +2374,7 @@ impl Editor {
         self.custom_context_menu = Some(Box::new(f))
     }
 
-    pub fn set_completion_provider(&mut self, provider: Option<Box<dyn CompletionProvider>>) {
+    pub fn set_completion_provider(&mut self, provider: Option<Rc<dyn CompletionProvider>>) {
         self.completion_provider = provider;
     }
 
@@ -2684,9 +2684,10 @@ impl Editor {
                     drop(context_menu);
 
                     let query = Self::completion_query(buffer, cursor_position);
-                    cx.spawn(async move |this, cx| {
+                    let completion_provider = self.completion_provider.clone();
+                    cx.spawn_in(window, async move |this, cx| {
                         completion_menu
-                            .filter(query.as_deref(), cx.background_executor().clone())
+                            .filter(query.as_deref(), completion_provider, this.clone(), cx)
                             .await;
 
                         this.update(cx, |this, cx| {
@@ -4960,15 +4961,16 @@ impl Editor {
         let word_search_range = buffer_snapshot.point_to_offset(min_word_search)
             ..buffer_snapshot.point_to_offset(max_word_search);
 
-        let provider = self
-            .completion_provider
-            .as_ref()
-            .filter(|_| !ignore_completion_provider);
+        let provider = if ignore_completion_provider {
+            None
+        } else {
+            self.completion_provider.clone()
+        };
         let skip_digits = query
             .as_ref()
             .map_or(true, |query| !query.chars().any(|c| c.is_digit(10)));
 
-        let (mut words, provided_completions) = match provider {
+        let (mut words, provided_completions) = match &provider {
             Some(provider) => {
                 let completions = provider.completions(
                     position.excerpt_id,
@@ -5071,7 +5073,9 @@ impl Editor {
                         } else {
                             None
                         },
-                        cx.background_executor().clone(),
+                        provider,
+                        editor.clone(),
+                        cx,
                     )
                     .await;
 
@@ -8651,6 +8655,11 @@ impl Editor {
         let context_menu = self.context_menu.borrow_mut().take();
         self.stale_inline_completion_in_menu.take();
         self.update_visible_inline_completion(window, cx);
+        if let Some(CodeContextMenu::Completions(_)) = &context_menu {
+            if let Some(completion_provider) = &self.completion_provider {
+                completion_provider.selection_changed(None, window, cx);
+            }
+        }
         context_menu
     }
 
@@ -11353,7 +11362,7 @@ impl Editor {
             .context_menu
             .borrow_mut()
             .as_mut()
-            .map(|menu| menu.select_first(self.completion_provider.as_deref(), cx))
+            .map(|menu| menu.select_first(self.completion_provider.as_deref(), window, cx))
             .unwrap_or(false)
         {
             return;
@@ -11477,7 +11486,7 @@ impl Editor {
             .context_menu
             .borrow_mut()
             .as_mut()
-            .map(|menu| menu.select_last(self.completion_provider.as_deref(), cx))
+            .map(|menu| menu.select_last(self.completion_provider.as_deref(), window, cx))
             .unwrap_or(false)
         {
             return;
@@ -11532,44 +11541,44 @@ impl Editor {
     pub fn context_menu_first(
         &mut self,
         _: &ContextMenuFirst,
-        _window: &mut Window,
+        window: &mut Window,
         cx: &mut Context<Self>,
     ) {
         if let Some(context_menu) = self.context_menu.borrow_mut().as_mut() {
-            context_menu.select_first(self.completion_provider.as_deref(), cx);
+            context_menu.select_first(self.completion_provider.as_deref(), window, cx);
         }
     }
 
     pub fn context_menu_prev(
         &mut self,
         _: &ContextMenuPrevious,
-        _window: &mut Window,
+        window: &mut Window,
         cx: &mut Context<Self>,
     ) {
         if let Some(context_menu) = self.context_menu.borrow_mut().as_mut() {
-            context_menu.select_prev(self.completion_provider.as_deref(), cx);
+            context_menu.select_prev(self.completion_provider.as_deref(), window, cx);
         }
     }
 
     pub fn context_menu_next(
         &mut self,
         _: &ContextMenuNext,
-        _window: &mut Window,
+        window: &mut Window,
         cx: &mut Context<Self>,
     ) {
         if let Some(context_menu) = self.context_menu.borrow_mut().as_mut() {
-            context_menu.select_next(self.completion_provider.as_deref(), cx);
+            context_menu.select_next(self.completion_provider.as_deref(), window, cx);
         }
     }
 
     pub fn context_menu_last(
         &mut self,
         _: &ContextMenuLast,
-        _window: &mut Window,
+        window: &mut Window,
         cx: &mut Context<Self>,
     ) {
         if let Some(context_menu) = self.context_menu.borrow_mut().as_mut() {
-            context_menu.select_last(self.completion_provider.as_deref(), cx);
+            context_menu.select_last(self.completion_provider.as_deref(), window, cx);
         }
     }
 
@@ -19615,6 +19624,8 @@ pub trait CompletionProvider {
         cx: &mut Context<Editor>,
     ) -> bool;
 
+    fn selection_changed(&self, _mat: Option<&StringMatch>, _window: &mut Window, _cx: &mut App) {}
+
     fn sort_completions(&self) -> bool {
         true
     }