Bug: [switch-exhaustiveness-check] - case of relying on an third party enums that are only imported as types

[salisbury-espinosa]

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• I have tried restarting my IDE and the issue persists.
• I have updated to the latest version of the packages.
• I have searched for related issues and found none that matched my issue.
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Playground Link

I couldn't attach a playground link because I needed two code source files for the case (to import one from the other) - only one is created in the sandbox...

Related links

issue
PR
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Repro Code

enum.ts

export enum DATA_TYPE {
  First = 0,
  Second = 1,
}

index.ts

import type { DATA_TYPE } from './enums';

export function test(type: DATA_TYPE) {
  switch (type) {
      case 0: { throw new Error('Not implemented yet: 0 case') }
      case 1: { throw new Error('Not implemented yet: 1 case') }
      default:
  }
}

ESLint Config

const {
    defineConfig,
} = require("eslint/config");

const tsParser = require("@typescript-eslint/parser");
const typescriptEslintEslintPlugin = require("@typescript-eslint/eslint-plugin");

module.exports = defineConfig([{
    languageOptions: {
        parser: tsParser,

        parserOptions: {
            project: "./tsconfig.json",
        },
    },

    plugins: {
        "@typescript-eslint": typescriptEslintEslintPlugin,
    },

    files: ["**/*.ts"],

    "rules": {
        "@typescript-eslint/no-unsafe-enum-comparison": "off",
        "@typescript-eslint/switch-exhaustiveness-check": ["error"],
    },
}]);

tsconfig

{
  "include": ["*.ts"],
  "compilerOptions": {
    "strictNullChecks": true
  }
}

Expected Result

success

Actual Result

  4:11  error  Switch is not exhaustive. Cases not matched: DATA_TYPE.First | DATA_TYPE.Second  @typescript-eslint/switch-exhaustiveness-check

✖ 1 problem (1 error, 0 warnings)

Additional Info

No response

[bradzacher]

This is expected.
Enums are supposed to be treated opaquely.

You're transparently comparing the values.
You need to use the enum instead.

[salisbury-espinosa]

You're transparently comparing the values.

@bradzacher

So why can't you make some option to lower the level just for enum types ?

this should work

export function test(type: DATA_TYPE) {
  switch (type) {
      case 0: { throw new Error('Not implemented yet: 0 case') }
      case 1: { throw new Error('Not implemented yet: 1 case') }
      default:
  }
}

and this one should threw up an error message ( Switch is not exhaustive. Cases not matched: DATA_TYPE.First )

export function test(type: DATA_TYPE) {
  switch (type) {
      case 1: { throw new Error('Not implemented yet: 1 case') }
      default:
  }
}

The main goal of this rule is to make code more "safe" (cover all values of union or enum).
And if we ALREADY have an external type and can only export it this way

import type { DATA_TYPE } from './enums';

, then why not provide the ability to adjust this behavior with some option?
It's about getting there, not about the ride....
pay attention: "@typescript-eslint/no-unsafe-enum-comparison": "off",