no-shadow False positive when declaring any TypeScript enum in JHipster app

Question

I want to use an enum in my app :

export const enum typeEnum {
  TVY = 'TVY',

  USER = 'USER',
}

At npm run webpack:build, I get the following error :

12:111 error 'typeEnum' is already declared in the upper scope no-shadow

I read on several link relative to this error that the solution was to add the following to the eslint rules :

  "no-shadow": "off",
  "@typescript-eslint/no-shadow": "error"

This is what I did, in the .eslintrc.json file :

{
  "plugins": ["@typescript-eslint/tslint"],
  "extends": ["jhipster"],
  "parserOptions": {
    "project": "./tsconfig.base.json"
  },
  "rules": {
    "@typescript-eslint/tslint/config": [
      "error",
      {
        "lintFile": "./tslint.json"
      }
    ],
    "@typescript-eslint/no-unused-vars": [
      "warn",
      {
        "vars": "all",
        "args": "after-used",
        "ignoreRestSiblings": false
      }
    ],
    "@typescript-eslint/no-non-null-assertion": "off",
    "no-shadow": "off",
    "@typescript-eslint/no-shadow": "error"
  }
}

But now, I get this error also at npm run:webpack:build :

myPath\src\main\webapp\app\vendor.ts [INFO] 1:1 error Definition for rule '@typescript-eslint/no-shadow' was not found @typescript-eslint/no-shadow

Do you know what I can do?

Thanks,

Manuela

score 30 · Answer 1 · answered Nov 09 '20 at 03:54

Turns out that you need to turn off the standard eslint rule, and instead use a TypeScript-specific value.

"no-shadow": "off",
"@typescript-eslint/no-shadow": ["error"],

This is noted here: https://github.com/typescript-eslint/typescript-eslint/issues/2483
eslint rule: https://eslint.org/docs/rules/no-shadow
TypeScript rule: https://github.com/typescript-eslint/typescript-eslint/blob/master/packages/eslint-plugin/docs/rules/no-shadow.md

(I just ran into this problem, made this change, and it solved it for me)

score 0 · Accepted Answer · answered Oct 23 '20 at 09:01

0

The error basically means you have another enum with the same name somewhere on level higher (probably in global scope). Try to rename your enum and look.

BTW. Switching off rules is a bad practice. TS/ES linters say where your code have problems. In most cases you have to fix the problem in the code instead of just shut up the linter.

answered Oct 23 '20 at 09:01

Roman Maksimov

1,537
1
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14

1

This is a false positive caused by enum. I don't have any other with the same name that's for sure. It's a known problem. Unfortunately, I didn't find any way to fix it without switching "no-shadow" rule to off. https://github.com/typescript-eslint/typescript-eslint/issues/2484 – Manuela CodingPadawan Oct 23 '20 at 09:10
Why do you do `const enum`? Why not just `enum`? – Roman Maksimov Oct 23 '20 at 09:14

score -1 · Answer 3 · answered Oct 23 '20 at 08:55

-1

Solution was to only add :

 "no-shadow": "off"

answered Oct 23 '20 at 08:55

Manuela CodingPadawan

436
1
8
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no-shadow False positive when declaring any TypeScript enum in JHipster app

3 Answers3