[types/convert-typeof-to-is-type]: Function insertion doubles the class comment.

[ElPrudi]

Every time this rule is triggered and inserts a function into the file where a class is, the class comment gets duplicated.

For example: X.ts:

/**
 * This is class X
 */
export default class X {

   public a(b): string {
          if (typeof b === 'number') return 'doStuff'
          return 'stuff'
   }
}

gets transformed into

/**
 * This is class X
 */
const isNumber = (x) => typeof x === 'number'

/**
 * This is class X
 */
export default class X {

   public a(b): string {
          if (isNumber(x)) return 'doStuff'
          return 'stuff'
   }
}

[coderaiser]

Could you please show me your .putout.json?

[ElPrudi]

I use eslint-plugin-putout and this is the putout part of it:

{
    "putout/putout": [
        2,
        {
            "plugins": ["apply-shorthand-properties", "conditions", "simplify-ternary", "types"],
            "rules": {
                "apply-shorthand-properties": [
                    "on",
                    {
                        "ignore": []
                    }
                ],
                "split-variable-declarations": "off",
                "new/remove-useless": "off",
                "remove-unused-variables": "off",
                "remove-console": "off",
                "convert-template-to-string": "off",
                "remove-useless-array-constructor": "off",
                "types/remove-double-negations": "off",
                "promises/remove-useless-async": "off",
                "convert-object-assign-to-merge-spread": "off",
                "apply-destructuring/array": "off",
                "apply-destructuring/object": "off",
                "promises/add-missing-await": "off",
                "typescript/remove-useless-parens": "off",
                "remove-useless-arguments/method": "off",
                "math/apply-exponentiation": [
                    "on",
                    {
                        "exclude": ["__a * __a", "__a * __a * __a", "__a * __a * __a * __a", "__a * __a * __a * __a * __a"]
                    }
                ]
            }
        }
    ],
    "putout/align-spaces": 0,
    "putout/remove-newline-from-empty-object": 0,
    "putout/add-newline-after-function-call": 0,
    "putout/add-newline-before-function-call": 0,
    "putout/add-newline-before-return": 0,
    "putout/add-newlines-between-specifiers": 0,
    "putout/add-newlines-between-types-in-union": 0,
    "putout/array-element-newline": 0,
    "putout/function-declaration-paren-newline": 0,
    "putout/keyword-spacing": 0,
    "putout/long-properties-destructuring": 0,
    "putout/multiple-properties-destructuring": 0,
    "putout/newline-function-call-arguments": 0,
    "putout/nonblock-statement-body-newline": 0,
    "putout/nonblock-statement-body-position": 0,
    "putout/object-property-newline": 0
}

[coderaiser]

I can't reproduce this with 1.ts:

/**
 * This is class X
 */
export default class X {

   public a(b): string {
          if (typeof b === 'number') return 'doStuff'
          return 'stuff'
   }
}

putout 1.ts --fix

Produces this result:

const isNumber = (a) => typeof a === 'number';

/**
 * This is class X
 */
export default class X {
    public a(b): string {
        if (isNumber(b))
            return 'doStuff';

        return 'stuff';
    }
}

[ElPrudi]

Found it. It only duplicates it, if you also have imports before that. If the inserted function becomes the first line in the file, it doesn't duplicate it.

[coderaiser]

Fixed in v30.6.0. Please re-install 🐊.

Is it works for you?

[ElPrudi]

Yes, it works now. Thank you very much :)