Eslint should report unnecessary client client component

[jakeleventhal]

Link to the code that reproduces this issue

#74520

To Reproduce

Consider the case of a very simple component like this:

'use client';

const MyComponent = () => {
  const [x] = useState('hello');
  return <div>{x}</div>;
};

The developer then realizes that the state variable was useless and removes it and is left with:

'use client';

const MyComponent = () => {
  return <div>hello</div>;
};

Now the component is a client component, but there is no reason for it to be. There should be a lint rule that checks for a useless client component in this case.

Current vs. Expected behavior

Should report error

Provide environment information

N/A applies to all versions

Which area(s) are affected? (Select all that apply)

Linting

Which stage(s) are affected? (Select all that apply)

next dev (local)

Additional context

No response

[github-actions]

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Useful Resources

• How to Contribute to Open Source (Next.js)
• How to create a Minimal, Complete, and Verifiable example
• Reporting a Next.js bug
• Next.js Triaging issues