Linter wants previously declared variable destructured during assignment

Tell us about your environment Windows 10

• ESLint Version: v4.12.0
• Node Version: v8.9.1
• npm Version: 5.5.

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

Please show your full configuration:

Configuration

{
  "env": {
    "es6": true,
    "node": true,
    "browser": true
  },
  "parserOptions": {
    "sourceType": "module",
    "ecmaVersion": 8
  },
  "rules": {
    "prefer-destructuring": ["error", {
      "VariableDeclarator": {
        "array": true,
        "object": true
      },
      "AssignmentExpression": {
        "array": true,
        "object": true
      }
    }, {
      "enforceForRenamedProperties": false
    }]
  }
}

What did you do? Please include the actual source code causing the issue, as well as the command that you used to run ESLint.

function potato(b) {
  let a;
  if(b) {
    a = b.a;
  }

  doThing(a); //Where a being undefined or not affects the downstream.
}

eslint .

What did you expect to happen? No error or warning.

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

..path...\test.js
  5:5  error  Use object destructuring  prefer-destructuring

✖ 1 problem (1 error, 0 warnings)

[platinumazure]

Unfortunately, since that’s a parsing error, the lint rules can’t even run at that point. I’m not aware of a good way to catch that and report a user-friendly message explaining the need for parentheses… Sorry.

On Nov 28, 2017 10:08 AM, “Krishna Glick” [e-mail] wrote:

Ah, that fixed it. Is there a linting rule to yell about that, or more a don’t be dumb kinda thing? 😃

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[krishnaglick]

Ah, that fixed it. Is there a linting rule to yell about that, or more a don't be dumb kinda thing? 😃