feat: Add Toast to React Aria Components (#7783)

* feat: Add Toast to React Aria Components

* Update useToast docs to reflect new aria pattern

* Apply suggestions from code review

Co-authored-by: Robert Snow <[email protected]>

* review updates

---------

Co-authored-by: Robert Snow <[email protected]>

Author: devongovett

lib/css.d.ts

@@ -0,0 +1,20 @@
+/*
+ * Copyright 2025 Adobe. All rights reserved.
+ * This file is licensed to you under the Apache License, Version 2.0 (the "License");
+ * you may not use this file except in compliance with the License. You may obtain a copy
+ * of the License at http://www.apache.org/licenses/LICENSE-2.0
+ *
+ * Unless required by applicable law or agreed to in writing, software distributed under
+ * the License is distributed on an "AS IS" BASIS, WITHOUT WARRANTIES OR REPRESENTATIONS
+ * OF ANY KIND, either express or implied. See the License for the specific language
+ * governing permissions and limitations under the License.
+ */
+
+declare module 'react' {
+  interface CSSProperties {
+    viewTransitionName?: string,
+    viewTransitionClass?: string
+  }
+}
+
+export {};

lib/viewTransitions.d.ts

@@ -0,0 +1,19 @@
+/*
+ * Copyright 2025 Adobe. All rights reserved.
+ * This file is licensed to you under the Apache License, Version 2.0 (the "License");
+ * you may not use this file except in compliance with the License. You may obtain a copy
+ * of the License at http://www.apache.org/licenses/LICENSE-2.0
+ *
+ * Unless required by applicable law or agreed to in writing, software distributed under
+ * the License is distributed on an "AS IS" BASIS, WITHOUT WARRANTIES OR REPRESENTATIONS
+ * OF ANY KIND, either express or implied. See the License for the specific language
+ * governing permissions and limitations under the License.
+ */
+
+interface Document {
+  startViewTransition(fn: () => void): ViewTransition;
+}
+  
+interface ViewTransition {
+  ready: Promise<void>;
+}

packages/@react-aria/toast/docs/useToast.mdx

@@ -35,7 +35,7 @@ keywords: [toast, notifications, alert, aria]
   packageData={packageData}
   componentNames={['useToastRegion', 'useToast']}
   sourceData={[
-    {type: 'W3C', url: 'https://www.w3.org/WAI/ARIA/apg/patterns/alert/'}
+    {type: 'W3C', url: 'https://www.w3.org/WAI/ARIA/apg/patterns/alertdialog/'}
   ]} />
 
 ## API
@@ -45,17 +45,17 @@ keywords: [toast, notifications, alert, aria]
 
 ## Features
 
-There is no built in way to toast notifications in HTML. <TypeLink links={docs.links} type={docs.exports.useToastRegion} /> and <TypeLink links={docs.links} type={docs.exports.useToast} /> help achieve accessible toasts that can be styled as needed.
+There is no built in way to display toast notifications in HTML. <TypeLink links={docs.links} type={docs.exports.useToastRegion} /> and <TypeLink links={docs.links} type={docs.exports.useToast} /> help achieve accessible toasts that can be styled as needed.
 
-* **Accessible** – Toasts follow the [ARIA alert pattern](https://www.w3.org/WAI/ARIA/apg/patterns/alert/). They are rendered in a [landmark region](https://www.w3.org/WAI/ARIA/apg/practices/landmark-regions/), which keyboard and screen reader users can easily jump to when an alert is announced.
+* **Accessible** – Toasts follow the [ARIA alertdialog pattern](https://www.w3.org/WAI/ARIA/apg/patterns/alertdialog/). They are rendered in a [landmark region](https://www.w3.org/WAI/ARIA/apg/practices/landmark-regions/), which keyboard and screen reader users can easily jump to when an alert is announced.
 * **Focus management** – When a toast unmounts, focus is moved to the next toast if any. Otherwise, focus is restored to where it was before navigating to the toast region.
 * **Priority queue** – Toasts are displayed according to a priority queue, displaying a configurable number of toasts at a time. The queue can either be owned by a provider component, or global.
 
 ## Anatomy
 
 <Anatomy role="img" aria-label="Toast anatomy diagram, showing the toast's title and close button within the toast region." />
 
-A toast region is an ARIA landmark region labeled "Notifications" by default. A toast region contains one or more visible toasts, in priority order. When the limit is reached, additional toasts are queued until the user dismisses one. Each toast is an ARIA alert element, containing the content of the notification and a close button.
+A toast region is an [ARIA landmark region](https://www.w3.org/WAI/ARIA/apg/practices/landmark-regions/) labeled "Notifications" by default. A toast region contains one or more visible toasts, in priority order. When the limit is reached, additional toasts are queued until the user dismisses one. Each toast is a non-modal ARIA [alertdialog](https://www.w3.org/WAI/ARIA/apg/patterns/alertdialog/), containing the content of the notification and a close button.
 
 Landmark regions including the toast container can be navigated using the keyboard by pressing the <Keyboard>F6</Keyboard> key to move forward, and the <Keyboard>Shift</Keyboard> + <Keyboard>F6</Keyboard> key to move backward. This provides an easy way for keyboard users to jump to the toasts from anywhere in the app. When the last toast is closed, keyboard focus is restored.
 

packages/@react-spectrum/toast/src/ToastContainer.tsx

@@ -39,19 +39,13 @@ export interface SpectrumToastOptions extends Omit<ToastOptions, 'priority'>, DO
 
 type CloseFunction = () => void;
 
-function wrapInViewTransition<R>(fn: () => R): R {
+function wrapInViewTransition(fn: () => void): void {
   if ('startViewTransition' in document) {
-    let result: R;
-    // @ts-expect-error
     document.startViewTransition(() => {
-      flushSync(() => {
-        result = fn();
-      });
+      flushSync(fn);
     }).ready.catch(() => {});
-    // @ts-ignore
-    return result;
   } else {
-    return fn();
+    fn();
   }
 }
 
@@ -141,8 +135,7 @@ export function ToastContainer(props: SpectrumToastContainerProps): ReactElement
                 key={toast.key}
                 className={classNames(toastContainerStyles, 'spectrum-ToastContainer-listitem')}
                 style={{
-                  // @ts-expect-error
-                  viewTransitionName: `_${toast.key.slice(2)}`,
+                  viewTransitionName: toast.key,
                   viewTransitionClass: classNames(
                     toastContainerStyles,
                     'toast',

packages/@react-stately/toast/src/useToastState.ts

@@ -18,7 +18,7 @@ export interface ToastStateProps {
   /** The maximum number of toasts to display at a time. */
   maxVisibleToasts?: number,
   /** Function to wrap updates in (i.e. document.startViewTransition()). */
-  wrapUpdate?: <R>(fn: () => R) => R
+  wrapUpdate?: (fn: () => void) => void
 }
 
 export interface ToastOptions {
@@ -88,20 +88,20 @@ export class ToastQueue<T> {
   private queue: QueuedToast<T>[] = [];
   private subscriptions: Set<() => void> = new Set();
   private maxVisibleToasts: number;
-  private wrapUpdate?: <R>(fn: () => R) => R;
+  private wrapUpdate?: (fn: () => void) => void;
   /** The currently visible toasts. */
   visibleToasts: QueuedToast<T>[] = [];
 
   constructor(options?: ToastStateProps) {
-    this.maxVisibleToasts = options?.maxVisibleToasts ?? 1;
+    this.maxVisibleToasts = options?.maxVisibleToasts ?? Infinity;
     this.wrapUpdate = options?.wrapUpdate;
   }
 
-  private runWithWrapUpdate<R>(fn: () => R): R {
+  private runWithWrapUpdate(fn: () => void): void {
     if (this.wrapUpdate) {
-      return this.wrapUpdate(fn);
+      this.wrapUpdate(fn);
     } else {
-      return fn();
+      fn();
     }
   }
 
@@ -113,7 +113,7 @@ export class ToastQueue<T> {
 
   /** Adds a new toast to the queue. */
   add(content: T, options: ToastOptions = {}) {
-    let toastKey = Math.random().toString(36);
+    let toastKey = '_' + Math.random().toString(36).slice(2);
     let toast: QueuedToast<T> = {
       ...options,
       content,