From cd32bac9e2815262d5710053eee86a7528649607 Mon Sep 17 00:00:00 2001
From: Rob Snow <rsnow@adobe.com>
Date: Wed, 8 Feb 2023 12:50:24 -0800
Subject: [PATCH 1/3] Fix React StrictMode Toast

---
 packages/@react-spectrum/toast/src/ToastContainer.tsx | 3 +--
 1 file changed, 1 insertion(+), 2 deletions(-)

diff --git a/packages/@react-spectrum/toast/src/ToastContainer.tsx b/packages/@react-spectrum/toast/src/ToastContainer.tsx
index 8532ee24565..92911eb08b2 100644
--- a/packages/@react-spectrum/toast/src/ToastContainer.tsx
+++ b/packages/@react-spectrum/toast/src/ToastContainer.tsx
@@ -73,10 +73,9 @@ export function ToastContainer(props: SpectrumToastContainerProps): ReactElement
   // We use a ref to do this, since it will have a stable identity
   // over the lifetime of the component.
   let ref = useRef();
-  toastProviders.add(ref);
 
-  // eslint-disable-next-line arrow-body-style
   useEffect(() => {
+    toastProviders.add(ref);
     return () => {
       // When this toast provider unmounts, reset all animations so that
       // when the new toast provider renders, it is seamless.

From 34fcf0398dbf4319d208074453ac170cb8fc5a0a Mon Sep 17 00:00:00 2001
From: Rob Snow <rsnow@adobe.com>
Date: Thu, 2 Mar 2023 09:55:48 -0800
Subject: [PATCH 2/3] Move to earlier effect

---
 packages/@react-spectrum/toast/package.json           | 1 +
 packages/@react-spectrum/toast/src/ToastContainer.tsx | 6 +++++-
 2 files changed, 6 insertions(+), 1 deletion(-)

diff --git a/packages/@react-spectrum/toast/package.json b/packages/@react-spectrum/toast/package.json
index 4347b032680..3a0584a5209 100644
--- a/packages/@react-spectrum/toast/package.json
+++ b/packages/@react-spectrum/toast/package.json
@@ -39,6 +39,7 @@
     "@react-aria/focus": "^3.11.0",
     "@react-aria/i18n": "^3.7.0",
     "@react-aria/toast": "3.0.0-alpha.1",
+    "@react-aria/utils": "^3.15.0",
     "@react-spectrum/button": "^3.12.0",
     "@react-spectrum/utils": "^3.9.0",
     "@react-stately/toast": "3.0.0-alpha.1",
diff --git a/packages/@react-spectrum/toast/src/ToastContainer.tsx b/packages/@react-spectrum/toast/src/ToastContainer.tsx
index 1cd050563c5..bb7b4ca16f1 100644
--- a/packages/@react-spectrum/toast/src/ToastContainer.tsx
+++ b/packages/@react-spectrum/toast/src/ToastContainer.tsx
@@ -15,6 +15,7 @@ import React, {ReactElement, ReactNode, useEffect, useRef} from 'react';
 import {SpectrumToastValue, Toast} from './Toast';
 import {Toaster} from './Toaster';
 import {ToastOptions, ToastQueue, useToastQueue} from '@react-stately/toast';
+import {useLayoutEffect} from '@react-aria/utils';
 import {useSyncExternalStore} from 'use-sync-external-store/shim/index.js';
 
 export interface SpectrumToastContainerProps extends AriaToastRegionProps {}
@@ -74,8 +75,11 @@ export function ToastContainer(props: SpectrumToastContainerProps): ReactElement
   // over the lifetime of the component.
   let ref = useRef();
 
-  useEffect(() => {
+  useLayoutEffect(() => {
     toastProviders.add(ref);
+  }, [toastProviders, ref]);
+
+  useEffect(() => {
     return () => {
       // When this toast provider unmounts, reset all animations so that
       // when the new toast provider renders, it is seamless.

From 273b4bb118a0697df98e6f0a8b78190823164003 Mon Sep 17 00:00:00 2001
From: Rob Snow <rsnow@adobe.com>
Date: Thu, 2 Mar 2023 15:30:58 -0800
Subject: [PATCH 3/3] fix implementation

---
 .../toast/src/ToastContainer.tsx              | 27 ++++++++++++++-----
 1 file changed, 21 insertions(+), 6 deletions(-)

diff --git a/packages/@react-spectrum/toast/src/ToastContainer.tsx b/packages/@react-spectrum/toast/src/ToastContainer.tsx
index bb7b4ca16f1..4fe560c0671 100644
--- a/packages/@react-spectrum/toast/src/ToastContainer.tsx
+++ b/packages/@react-spectrum/toast/src/ToastContainer.tsx
@@ -49,8 +49,25 @@ export function clearToastQueue() {
   globalToastQueue = null;
 }
 
-let toastProviders = new Set();
+
+let store = new Set();
+let toastProviders = {
+  add: (ref) => {
+    store.add(ref);
+    emitChange();
+  },
+  delete: (ref) => {
+    store.delete(ref);
+    emitChange();
+  },
+  values: () => store.values()
+};
 let subscriptions = new Set<() => void>();
+function emitChange() {
+  for (let fn of subscriptions) {
+    fn();
+  }
+}
 function subscribe(fn: () => void) {
   subscriptions.add(fn);
   return () => subscriptions.delete(fn);
@@ -70,7 +87,8 @@ function useActiveToastContainer() {
  */
 export function ToastContainer(props: SpectrumToastContainerProps): ReactElement {
   // Track all toast provider instances in a set.
-  // Only the first one will actually render.
+  // All will render null at first. Once they have been registered, all will re-render
+  // and the last one will become the active toast provider, the rest will still return null.
   // We use a ref to do this, since it will have a stable identity
   // over the lifetime of the component.
   let ref = useRef();
@@ -87,13 +105,10 @@ export function ToastContainer(props: SpectrumToastContainerProps): ReactElement
         toast.animation = null;
       }
 
-      // Remove this toast provider, and call subscriptions.
+      // Remove this toast provider.
       // This will cause all other instances to re-render,
       // and the first one to become the new active toast provider.
       toastProviders.delete(ref);
-      for (let fn of subscriptions) {
-        fn();
-      }
     };
   }, []);