test: Add test coverage for ensuredForwardRef

tests/useEnsuredForwardedRef.test.tsx

@@ -2,7 +2,7 @@ import React, { useRef } from 'react';
 import ReactDOM from 'react-dom';
 import { renderHook } from '@testing-library/react-hooks';
 import TestUtils from 'react-dom/test-utils';
-import { useEnsuredForwardedRef } from '../src';
+import { ensuredForwardRef, useEnsuredForwardedRef } from '../src';
 
 let container: HTMLDivElement;
 
@@ -51,3 +51,24 @@ test('should return a valid ref when the forwarded ref is undefined', () => {
 
   expect(ensuredRef.current.id).toBe('test_id');
 });
+
+test('should return a valid ref when using the wrapper function style', () => {
+  const { result } = renderHook(() => {
+    const initialRef = useRef<HTMLDivElement | null>(null);
+
+    const WrappedComponent = ensuredForwardRef<HTMLDivElement>((_props, ref) => {
+      return <div id="test_id" ref={ref} />;
+    });
+
+    TestUtils.act(() => {
+      ReactDOM.render(<WrappedComponent ref={initialRef} />, container);
+    });
+
+    return { initialRef };
+  });
+
+  const { initialRef } = result.current;
+
+  expect(initialRef.current).toBeTruthy();
+  expect(initialRef.current?.id).toBe('test_id');
+});