From da6a26548b8aa13fbe39a123bb652c0e35b4dd37 Mon Sep 17 00:00:00 2001
From: Brent Erickson <berickson1@users.noreply.github.com>
Date: Tue, 12 Feb 2019 13:39:35 -0800
Subject: [PATCH] Fix crash in RNTester when removing/developing tests (#23406)

Summary:
Ensure that the current openExample (stored in AsyncStorage) exists in the module list.

It's possible for the example to be missing if a test was removed & previously open in RNTester OR when actively developing RNTester tests & switching between branches

[General] [Fixed] - Potential crash in RNTester when removing/developing test cases
Pull Request resolved: https://github.com/facebook/react-native/pull/23406

Differential Revision: D14055695

Pulled By: cpojer

fbshipit-source-id: 6cf00e097e934f7a342e7d210b6319e1cba142ca
---
 RNTester/js/RNTesterApp.ios.js | 2 +-
 1 file changed, 1 insertion(+), 1 deletion(-)

diff --git a/RNTester/js/RNTesterApp.ios.js b/RNTester/js/RNTesterApp.ios.js
index e6bf7457aac..2ef1ff817e2 100644
--- a/RNTester/js/RNTesterApp.ios.js
+++ b/RNTester/js/RNTesterApp.ios.js
@@ -110,7 +110,7 @@ class RNTesterApp extends React.Component<Props, RNTesterNavigationState> {
     }
     if (this.state.openExample) {
       const Component = RNTesterList.Modules[this.state.openExample];
-      if (Component.external) {
+      if (Component && Component.external) {
         return <Component onExampleExit={this._handleBack} />;
       } else {
         return (