How to mock a private method in Jest while testing a React component?
I've searched everywhere and can't find a clear answer. I'm trying to unit test a React component that has a private method, and I'm running into some issues with mocking it using Jest. My component looks like this: ```javascript import React from 'react'; class MyComponent extends React.Component { handleClick() { this.privateMethod(); } privateMethod() { return 'Hello'; } render() { return <button onClick={() => this.handleClick()}>Click me</button>; } } export default MyComponent; ``` In my test file, I'm trying to spy on `privateMethod` to see if it gets called when the button is clicked. However, since `privateMethod` is not directly exposed, Jest doesn't allow me to mock it directly, and I get the following behavior: ``` TypeError: want to read properties of undefined (reading 'privateMethod') ``` Here's what I've tried so far: - I attempted to use `jest.spyOn(MyComponent.prototype, 'privateMethod')`, but it doesn't work as expected since `privateMethod` isn't being called directly in the test. - I also looked into using `jest.fn()` to mock the instance method directly, but I'm not sure how to apply it to a private function. - Lastly, I tried refactoring the private method into a separate utility class so I could mock it easily, but that feels like overkill for this situation. I'm using Jest 27.x and React 17.x. Is there a recommended way to handle this scenario without having to expose the private method or refactor too much? Any best practices for testing private methods in this context would be appreciated!