[react-transition-group] Add types for config (#38770)

* [react-transition-group] Add types for config

* [react-transition-group] Add test for changing config

types/react-transition-group/config.d.ts

@@ -0,0 +1,6 @@
+export interface Config {
+    disabled: boolean;
+}
+
+declare const config: Config;
+export default config;

types/react-transition-group/index.d.ts

@@ -3,6 +3,7 @@
 // Definitions by: Karol Janyst <https://github.com/LKay>
 //                 Epskampie <https://github.com/Epskampie>
 //                 Masafumi Koba <https://github.com/ybiquitous>
+//                 tu4mo <https://github.com/tu4mo>
 // Definitions: https://github.com/DefinitelyTyped/DefinitelyTyped
 // TypeScript Version: 2.8
 
@@ -10,3 +11,4 @@ export { default as Transition } from './Transition';
 export { default as CSSTransition } from './CSSTransition';
 export { default as TransitionGroup } from './TransitionGroup';
 export { default as SwitchTransition } from './SwitchTransition';
+export { default as config } from './config';

types/react-transition-group/react-transition-group-tests.tsx

@@ -1,7 +1,7 @@
 import * as React from "react";
 import { UNMOUNTED, EXITED, ENTERING, ENTERED, EXITING, TransitionStatus } from "react-transition-group/Transition";
 import { modes } from "react-transition-group/SwitchTransition";
-import { Transition, CSSTransition, TransitionGroup, SwitchTransition } from "react-transition-group";
+import { Transition, CSSTransition, TransitionGroup, SwitchTransition, config } from "react-transition-group";
 
 interface ContainerProps {
     theme: string;
@@ -213,3 +213,5 @@ const Test: React.StatelessComponent = () => {
         </>
     );
 };
+
+config.disabled = false;

types/react-transition-group/tsconfig.json

@@ -25,6 +25,7 @@
         "Transition.d.ts",
         "TransitionGroup.d.ts",
         "SwitchTransition.d.ts",
-        "react-transition-group-tests.tsx"
+        "react-transition-group-tests.tsx",
+        "config.d.ts"
     ]
 }