[react-big-calendar] add dateFnsLocalizer() (#42250)

* add dateFnsLocalizer()

* test

types/react-big-calendar/index.d.ts

@@ -337,6 +337,7 @@ export interface components {
 }
 export function globalizeLocalizer(globalizeInstance: object): DateLocalizer;
 export function momentLocalizer(momentInstance: object): DateLocalizer;
+export function dateFnsLocalizer(config: object): DateLocalizer;
 export interface Navigate {
     PREVIOUS: 'PREV';
     NEXT: 'NEXT';

types/react-big-calendar/react-big-calendar-tests.tsx

@@ -5,6 +5,7 @@ import {
     CalendarProps,
     momentLocalizer,
     globalizeLocalizer,
+    dateFnsLocalizer,
     move,
     Views,
     components,
@@ -22,6 +23,7 @@ import withDragAndDrop from "react-big-calendar/lib/addons/dragAndDrop";
 // Don't want to add this as a dependency, because it is only used for tests.
 declare const globalize: any;
 declare const moment: any;
+declare const dateFnsConfig: any;
 
 declare const allViews: View[];
 
@@ -78,6 +80,27 @@ class CalendarResource {
     ReactDOM.render(<Basic localizer={localizer} />, document.body);
 }
 
+// date-fns Example Test
+{
+    interface Props {
+        localizer: DateLocalizer;
+    }
+    const Basic = ({ localizer }: Props) => (
+        <Calendar
+            events={getEvents()}
+            views={allViews}
+            step={60}
+            showMultiDayTimes
+            defaultDate={new Date(2015, 3, 1)}
+            localizer={localizer}
+        />
+    );
+
+    const localizer = dateFnsLocalizer(dateFnsConfig);
+
+    ReactDOM.render(<Basic localizer={localizer} />, document.body);
+}
+
 // Drag and Drop Example Test
 {
     interface Props {