jsx-uses-vars is confused by shadowed variables.

[Wilfred]

Given the following code:

import React from 'react';
import {FooPicker} from '../FooPicker';

function myTest() {
  const FooPicker = require('../FooPicker').default;
  return <FooPicker />;
}

myTest();

and the following .eslintrc.json:

{
    "env": {
        "node": true
    },
    "parserOptions": {
        "ecmaVersion": 6,
        "ecmaFeatures": {
            "jsx": true,
            "impliedStrict": true
        },
        "sourceType": "module"
    },
    "rules": {
        "no-unused-vars": "warn",
        "react/jsx-uses-vars": "warn",
        "react/jsx-uses-react": "warn"
    },
    "plugins": [
        "react"
    ]
}

No warnings are generated. We should warn on the import {FooPicker}, as it's unused.

Possibly related: #716.

[Wilfred]

Thanks! :)