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Destructuring two variables and reassigning the value of one is hard with let and const

See original GitHub issue

Tell us about your environment

ESLint Version: 3.16.1
Node Version: v6.6.0
npm Version: 3.10.3

What parser (default, Babel-ESLint, etc.) are you using? default

Please show your full configuration:

module.exports = {
  "env": {
    "browser": true,
    "es6": true
  },
  "extends": "eslint:recommended",
  "parserOptions": {
    "sourceType": "module",
    "ecmaFeatures": {
      "experimentalObjectRestSpread": true
    }
  },
  "rules": {
    "prefer-const": ["error", {
      "destructuring": "any",
      "ignoreReadBeforeAssign": false
    }],
    "no-console": "off"
  }
};

What did you do? Please include the actual source code causing the issue.

I have a basic test case of the problem in this code:

const props = {
  name: "Eric",
  age: 30,
  occupation: "Artist"
}

let { name, age } = props;
age = 3;

console.log(name);
console.log(age);

ESLint says that let { name, age } = props; is a problem and should use const.

Here, two variables are created via destructuring syntax, and one is later reassigned but the other is not.

Fixing the code as the rule suggests means using const, which creates a syntax error.

What did you expect to happen?

I’m not sure 😃

What actually happened? Please include the actual, raw output from ESLint.

$ ./node_modules/.bin/eslint app.js

/Users/eric/Desktop/eslint/app.js
  7:7  error  'name' is never reassigned. Use 'const' instead  prefer-const

✖ 1 problem (1 error, 0 warnings)