From 14778f64017d46e6ee6d73218926d7f35281955e Mon Sep 17 00:00:00 2001
From: Andrei Zhaleznichenka <zhalea@amazon.de>
Date: Thu, 12 Sep 2024 13:24:24 +0200
Subject: [PATCH] avoid calling listener when provider is not defined

---
 pages/alert/runtime-content.page.tsx          |  4 ++--
 .../controllers/alert-flash-content.ts        | 19 +++++++++++--------
 .../helpers/use-discovered-content.tsx        |  2 +-
 3 files changed, 14 insertions(+), 11 deletions(-)

diff --git a/pages/alert/runtime-content.page.tsx b/pages/alert/runtime-content.page.tsx
index 735b2706b5d..589d2b552bd 100644
--- a/pages/alert/runtime-content.page.tsx
+++ b/pages/alert/runtime-content.page.tsx
@@ -1,7 +1,7 @@
 // Copyright Amazon.com, Inc. or its affiliates. All Rights Reserved.
 // SPDX-License-Identifier: Apache-2.0
 
-import React, { useContext, useState } from 'react';
+import React, { useContext, useMemo, useState } from 'react';
 import { render, unmountComponentAtNode } from 'react-dom';
 
 import {
@@ -72,7 +72,7 @@ export default function () {
   const [unrelatedState, setUnrelatedState] = useState(false);
   const [contentSwapped, setContentSwapped] = useState(false);
 
-  const content1 = loading ? <Box>Loading...</Box> : <Box>Content</Box>;
+  const content1 = useMemo(() => (loading ? <Box>Loading...</Box> : <Box>Content</Box>), [loading]);
   const content2 = loading ? <Box>Loading...</Box> : <Box>There was an error: Access denied because of XYZ</Box>;
 
   return (
diff --git a/src/internal/plugins/controllers/alert-flash-content.ts b/src/internal/plugins/controllers/alert-flash-content.ts
index 6d339d3b85d..ea9722ece16 100644
--- a/src/internal/plugins/controllers/alert-flash-content.ts
+++ b/src/internal/plugins/controllers/alert-flash-content.ts
@@ -35,7 +35,7 @@ export interface AlertFlashContentConfig {
   runReplacer: (context: AlertFlashContentContext, replacementApi: ReplacementApi) => AlertFlashContentResult;
 }
 
-export type AlertFlashContentRegistrationListener = (provider?: AlertFlashContentConfig) => void | (() => void);
+export type AlertFlashContentRegistrationListener = (provider: AlertFlashContentConfig) => () => void;
 
 export interface AlertFlashContentApiPublic {
   registerContentReplacer(config: AlertFlashContentConfig): void;
@@ -48,14 +48,16 @@ export interface AlertFlashContentApiInternal {
 
 export class AlertFlashContentController {
   #listeners: Array<AlertFlashContentRegistrationListener> = [];
-  #cleanups = new Map<AlertFlashContentRegistrationListener, null | (() => void)>();
+  #cleanups = new Map<AlertFlashContentRegistrationListener, () => void>();
   #provider?: AlertFlashContentConfig;
 
   #scheduleUpdate = debounce(
     () =>
       this.#listeners.forEach(listener => {
-        const cleanup = listener(this.#provider) ?? null;
-        this.#cleanups.set(listener, cleanup);
+        if (this.#provider) {
+          const cleanup = listener(this.#provider);
+          this.#cleanups.set(listener, cleanup);
+        }
       }),
     0
   );
@@ -78,12 +80,13 @@ export class AlertFlashContentController {
   };
 
   onContentRegistered = (listener: AlertFlashContentRegistrationListener) => {
-    const cleanup = listener(this.#provider);
-    this.#listeners.push(listener);
-    if (cleanup) {
+    if (this.#provider) {
+      const cleanup = listener(this.#provider);
+      this.#listeners.push(listener);
       this.#cleanups.set(listener, cleanup);
+    } else {
+      this.#listeners.push(listener);
     }
-
     return () => {
       this.#cleanups.get(listener)?.();
       this.#listeners = this.#listeners.filter(item => item !== listener);
diff --git a/src/internal/plugins/helpers/use-discovered-content.tsx b/src/internal/plugins/helpers/use-discovered-content.tsx
index 2de50d8999b..3b46c4d7afb 100644
--- a/src/internal/plugins/helpers/use-discovered-content.tsx
+++ b/src/internal/plugins/helpers/use-discovered-content.tsx
@@ -45,7 +45,7 @@ export function createUseDiscoveredContent(
           return true;
         }
 
-        mountedProvider.current = provider?.runReplacer(context, {
+        mountedProvider.current = provider.runReplacer(context, {
           hideHeader() {
             if (checkMounted('hideHeader')) {
               setFoundHeaderReplacement('remove');