I am using eslint 4.17.0, which is reporting an issue that number is never reassigned, however I am reassigning it. Can someone explain why do I need to use const in this case?

let test = {
    'number': 1,
    'string': 'asd',
};
test.number = 99;

console.log(test.number);
// output: 99

{
    "parser": "babel-eslint",
    "env": {
        "browser": true
    },
    "extends": [
        "google"
    ],
    "rules": {
        "prefer-const": 2

    },
    "parserOptions": {
        "ecmaVersion": 6,
        "sourceType": "module"
    }
}

[eslint] 'test' is never reassigned. Use 'const' insted. (prefer-const)

I am using eslint 4.17.0, which is reporting an issue that number is never reassigned, however I am reassigning it. Can someone explain why do I need to use const in this case?

let test = {
    'number': 1,
    'string': 'asd',
};
test.number = 99;

console.log(test.number);
// output: 99

{
    "parser": "babel-eslint",
    "env": {
        "browser": true
    },
    "extends": [
        "google"
    ],
    "rules": {
        "prefer-const": 2

    },
    "parserOptions": {
        "ecmaVersion": 6,
        "sourceType": "module"
    }
}

[eslint] 'test' is never reassigned. Use 'const' insted. (prefer-const)

• javascript
• eslint

• eslint.org/docs/rules/prefer-const – fdomn-m Commented Feb 9, 2018 at 14:03
• 1 It's because test is not changed. You're changing test.number, not test. – fdomn-m Commented Feb 9, 2018 at 14:38
• 3 Also, your error message does not match your question title. One says test (correctly) the title says "number" which is changed and is not in the warning. – fdomn-m Commented Feb 9, 2018 at 14:39
• Dang, I was looking for this rule. Somehow VSCode stopped suggesting this to me. Looks like it was just this project where I don't have my usual eslint rules