Add Context::read_window, WindowHandle::root, and change ViewContext.view() to return a reference

crates/gpui2/src/app/async_context.rs

@@ -66,6 +66,16 @@ impl Context for AsyncAppContext {
         let mut lock = app.borrow_mut();
         lock.update_window(window, f)
     }
+
+    fn read_window<R>(
+        &self,
+        window: &AnyWindowHandle,
+        read: impl FnOnce(AnyView, &AppContext) -> R,
+    ) -> Result<R> {
+        let app = self.app.upgrade().context("app was released")?;
+        let lock = app.borrow();
+        lock.read_window(window, read)
+    }
 }
 
 impl AsyncAppContext {
@@ -250,6 +260,14 @@ impl Context for AsyncWindowContext {
     {
         self.app.read_model(handle, read)
     }
+
+    fn read_window<R>(
+        &self,
+        window: &AnyWindowHandle,
+        read: impl FnOnce(AnyView, &AppContext) -> R,
+    ) -> Result<R> {
+        self.app.read_window(window, read)
+    }
 }
 
 impl VisualContext for AsyncWindowContext {

crates/gpui2/src/app/model_context.rs

@@ -239,6 +239,14 @@ impl<'a, T> Context for ModelContext<'a, T> {
     {
         self.app.read_model(handle, read)
     }
+
+    fn read_window<R>(
+        &self,
+        window: &AnyWindowHandle,
+        read: impl FnOnce(AnyView, &AppContext) -> R,
+    ) -> Result<R> {
+        self.app.read_window(window, read)
+    }
 }
 
 impl<T> Borrow<AppContext> for ModelContext<'_, T> {

crates/gpui2/src/app/test_context.rs

@@ -58,6 +58,15 @@ impl Context for TestAppContext {
         let app = self.app.borrow();
         app.read_model(handle, read)
     }
+
+    fn read_window<R>(
+        &self,
+        window: &AnyWindowHandle,
+        read: impl FnOnce(AnyView, &AppContext) -> R,
+    ) -> Result<R> {
+        let app = self.app.borrow();
+        app.read_window(window, read)
+    }
 }
 
 impl TestAppContext {
@@ -146,6 +155,11 @@ impl TestAppContext {
         Some(read(lock.try_global()?, &lock))
     }
 
+    pub fn set_global<G: 'static, R>(&mut self, global: G) {
+        let mut lock = self.app.borrow_mut();
+        lock.set_global(global);
+    }
+
     pub fn update_global<G: 'static, R>(
         &mut self,
         update: impl FnOnce(&mut G, &mut AppContext) -> R,