DatePicker: Fix crash when navigating between months (#31751)

packages/components/src/date-time/date.js

@@ -82,7 +82,7 @@ class DatePicker extends Component {
 	}
 
 	onMonthPreviewedHandler( newMonthDate ) {
-		this.props?.onMonthPreviewed( newMonthDate.toISOString() );
+		this.props.onMonthPreviewed?.( newMonthDate.toISOString() );
 		this.keepFocusInside();
 	}
 

packages/components/src/date-time/stories/date.js

@@ -0,0 +1,17 @@
+/**
+ * Internal dependencies
+ */
+import DatePicker from '../date';
+
+/**
+ * WordPress dependencies
+ */
+import { useState } from '@wordpress/element';
+
+export default { title: 'Components/DatePicker', component: DatePicker };
+
+export const _default = () => {
+	const [ date, setDate ] = useState();
+
+	return <DatePicker currentDate={ date } onChange={ setDate } />;
+};