Pass a MutableAppContext to Element::layout and ::dispatch_event

We need to mutate the app in these cases to relay layout state, so this just makes things easier. We won't be able to perform layout in parallel but it's questionable whether we'll ever actually do that. If we do, we can revisit.

Co-Authored-By: Antonio Scandurra <me@as-cii.com>
Co-Authored-By: Max Brunsfeld <maxbrunsfeld@gmail.com>

zed/src/editor/element.rs

@@ -38,8 +38,9 @@ impl EditorElement {
         cx: &mut EventContext,
     ) -> bool {
         if paint.text_bounds.contains_point(position) {
-            let view = self.view(cx.app);
-            let position = paint.point_for_position(view, layout, position, cx.font_cache, cx.app);
+            let view = self.view(cx.app.as_ref());
+            let position =
+                paint.point_for_position(view, layout, position, cx.font_cache, cx.app.as_ref());
             cx.dispatch_action("buffer:select", SelectAction::Begin { position, add: cmd });
             true
         } else {
@@ -48,7 +49,7 @@ impl EditorElement {
     }
 
     fn mouse_up(&self, _position: Vector2F, cx: &mut EventContext) -> bool {
-        if self.view(cx.app).is_selecting() {
+        if self.view(cx.app.as_ref()).is_selecting() {
             cx.dispatch_action("buffer:select", SelectAction::End);
             true
         } else {
@@ -63,7 +64,7 @@ impl EditorElement {
         paint: &mut PaintState,
         cx: &mut EventContext,
     ) -> bool {
-        let view = self.view(cx.app);
+        let view = self.view(cx.app.as_ref());
 
         if view.is_selecting() {
             let rect = paint.text_bounds;
@@ -93,22 +94,21 @@ impl EditorElement {
                 ))
             }
 
-            cx.dispatch_action(
-                "buffer:select",
-                SelectAction::Update {
-                    position: paint.point_for_position(
-                        view,
-                        layout,
-                        position,
-                        cx.font_cache,
-                        cx.app,
-                    ),
-                    scroll_position: (view.scroll_position() + scroll_delta).clamp(
-                        Vector2F::zero(),
-                        layout.scroll_max(view, cx.font_cache, cx.text_layout_cache, cx.app),
-                    ),
-                },
-            );
+            let action = SelectAction::Update {
+                position: paint.point_for_position(
+                    view,
+                    layout,
+                    position,
+                    cx.font_cache,
+                    cx.app.as_ref(),
+                ),
+                scroll_position: (view.scroll_position() + scroll_delta).clamp(
+                    Vector2F::zero(),
+                    layout.scroll_max(view, cx.font_cache, cx.text_layout_cache, cx.app),
+                ),
+            };
+
+            cx.dispatch_action("buffer:select", action);
             true
         } else {
             false
@@ -326,7 +326,7 @@ impl Element for EditorElement {
         constraint: SizeConstraint,
         cx: &mut LayoutContext,
     ) -> (Vector2F, Self::LayoutState) {
-        let app = cx.app;
+        let app = &mut cx.app;
         let mut size = constraint.max;
         if size.y().is_infinite() {
             let view = self.view(app);

zed/src/file_finder.rs

@@ -124,6 +124,7 @@ impl FileFinder {
             self.list_state.clone(),
             self.matches.len(),
             move |mut range, items, cx| {
+                let cx = cx.as_ref();
                 let finder = handle.upgrade(cx).unwrap();
                 let finder = finder.read(cx);
                 let start = range.start;