Flat Config Format

[zN3utr4l]

#1299 (comment)

The new version still throw exception:

yarn lint
  eslint:cli CLI args: [ '--debug', '.', '--fix' ] +0ms
  eslint:cli Using flat config? true +5ms
  eslint:cli Running on files +6ms
  eslint:eslint Using file patterns: . +0ms
  eslint:eslint Searching for eslint.config.js +0ms
  eslint:eslint Loading config from G:\MyProj\proj\client\eslint.config.js +5ms
  eslint:eslint Config file URL is file:///G:/MyProj/proj/client/eslint.config.js +0ms
  eslint:rules Loading rule 'array-bracket-newline' (remaining=289) +0ms
  eslint:rules Loading rule 'array-bracket-spacing' (remaining=288) +15ms
  eslint:rules Loading rule 'array-element-newline' (remaining=287) +6ms
  eslint:rules Loading rule 'arrow-spacing' (remaining=286) +6ms
  eslint:rules Loading rule 'block-spacing' (remaining=285) +35ms
  eslint:rules Loading rule 'brace-style' (remaining=284) +6ms
  eslint:rules Loading rule 'camelcase' (remaining=283) +4ms
  eslint:rules Loading rule 'comma-dangle' (remaining=282) +3ms
  eslint:rules Loading rule 'comma-spacing' (remaining=281) +7ms
  eslint:rules Loading rule 'comma-style' (remaining=280) +5ms
  eslint:rules Loading rule 'dot-location' (remaining=279) +12ms
  eslint:rules Loading rule 'dot-notation' (remaining=278) +5ms
  eslint:rules Loading rule 'eqeqeq' (remaining=277) +5ms
  eslint:rules Loading rule 'func-call-spacing' (remaining=276) +4ms
  eslint:rules Loading rule 'key-spacing' (remaining=275) +15ms
  eslint:rules Loading rule 'keyword-spacing' (remaining=274) +12ms
  eslint:rules Loading rule 'multiline-ternary' (remaining=273) +10ms
  eslint:rules Loading rule 'no-console' (remaining=272) +9ms
  eslint:rules Loading rule 'no-constant-condition' (remaining=271) +3ms
  eslint:rules Loading rule 'no-empty-pattern' (remaining=270) +17ms
  eslint:rules Loading rule 'no-extra-parens' (remaining=269) +6ms
  eslint:rules Loading rule 'no-loss-of-precision' (remaining=268) +9ms
  eslint:rules Loading rule 'no-restricted-syntax' (remaining=267) +21ms
  eslint:rules Loading rule 'no-sparse-arrays' (remaining=266) +7ms
  eslint:rules Loading rule 'no-useless-concat' (remaining=265) +19ms
  eslint:rules Loading rule 'object-curly-newline' (remaining=264) +8ms
  eslint:rules Loading rule 'object-curly-spacing' (remaining=263) +5ms
  eslint:rules Loading rule 'object-property-newline' (remaining=262) +4ms
  eslint:rules Loading rule 'object-shorthand' (remaining=261) +4ms
  eslint:rules Loading rule 'operator-linebreak' (remaining=260) +5ms
  eslint:rules Loading rule 'prefer-template' (remaining=259) +11ms
  eslint:rules Loading rule 'quote-props' (remaining=258) +4ms
  eslint:rules Loading rule 'space-in-parens' (remaining=257) +20ms
  eslint:rules Loading rule 'space-infix-ops' (remaining=256) +5ms
  eslint:rules Loading rule 'space-unary-ops' (remaining=255) +5ms
  eslint:rules Loading rule 'template-curly-spacing' (remaining=254) +5ms
  eslint:rules Loading rule 'consistent-return' (remaining=253) +630ms
  eslint:rules Loading rule 'indent' (remaining=252) +24ms
  eslint:rules Loading rule 'init-declarations' (remaining=251) +7ms
  eslint:rules Loading rule 'lines-around-comment' (remaining=250) +4ms
  eslint:rules Loading rule 'lines-between-class-members' (remaining=249) +4ms
  eslint:rules Loading rule 'max-params' (remaining=248) +3ms
  eslint:rules Loading rule 'no-dupe-class-members' (remaining=247) +24ms
  eslint:rules Loading rule 'no-empty-function' (remaining=246) +4ms
  eslint:rules Loading rule 'no-extra-semi' (remaining=245) +5ms
  eslint:rules Loading rule 'no-invalid-this' (remaining=244) +15ms
  eslint:rules Loading rule 'no-loop-func' (remaining=243) +3ms
  eslint:rules Loading rule 'no-magic-numbers' (remaining=242) +4ms
  eslint:rules Loading rule 'no-restricted-imports' (remaining=241) +19ms
  eslint:rules Loading rule 'no-unused-expressions' (remaining=240) +42ms
  eslint:rules Loading rule 'no-useless-constructor' (remaining=239) +5ms
  eslint:rules Loading rule 'prefer-destructuring' (remaining=238) +15ms
  eslint:rules Loading rule 'quotes' (remaining=237) +44ms
  eslint:rules Loading rule 'semi' (remaining=236) +11ms
  eslint:rules Loading rule 'space-before-blocks' (remaining=235) +4ms

Oops! Something went wrong! :(

ESLint: 9.3.0

Error: This method cannot be used with flat config. Add your entries directly into the config array.
    at assertEslintrcConfig (G:\MyProj\proj\client\node_modules\eslint\lib\linter\linter.js:1256:15)
    at Linter.getRules (G:\MyProj\proj\client\node_modules\eslint\lib\linter\linter.js:2185:9)
    at Object.<anonymous> (G:\MyProj\proj\client\node_modules\eslint-config-love\lib\index.js:418:61)
    at Module._compile (node:internal/modules/cjs/loader:1364:14)
    at Module._extensions..js (node:internal/modules/cjs/loader:1422:10)
    at Module.load (node:internal/modules/cjs/loader:1203:32)
    at Module._load (node:internal/modules/cjs/loader:1019:12)
    at ModuleWrap.<anonymous> (node:internal/modules/esm/translators:203:29)
    at ModuleJob.run (node:internal/modules/esm/module_job:195:25)
    at async ModuleLoader.import (node:internal/modules/esm/loader:337:24)

eslint.config.js

import pluginVue from 'eslint-plugin-vue'
import globals from 'globals'

import { FlatCompat } from '@eslint/eslintrc'
import pluginJs from '@eslint/js'
import eslintLove from 'eslint-config-love'

import path from 'path'
import { fileURLToPath } from 'url'

// mimic CommonJS variables -- not needed if using CommonJS
const _filename = fileURLToPath(import.meta.url)
const _dirname = path.dirname(_filename)
const compat = new FlatCompat({ baseDirectory: _dirname, recommendedConfig: pluginJs.configs.recommended, allConfig: pluginJs.configs.all })

export default [
  {
    languageOptions: {
      globals: {
        __statics: 'readonly',
        __QUASAR_SSR__: 'readonly',
        __QUASAR_SSR_SERVER__: 'readonly',
        __QUASAR_SSR_CLIENT__: 'readonly',
        __QUASAR_SSR_PWA__: 'readonly',
        ...globals.browser
      },
      parserOptions: {
        extraFileExtensions: ['.vue']
      }
    },
    ignores: [
      './dist/*',
      './.quasar/*',
      './node_modules/*',
      './src-capacitor/*',
      './src-cordova/*',
      './src-electron/*',
      './quasar.config.*.temporary.compiled*'
    ]
  },
  ...compat.extends('prettier'),
  ...pluginVue.configs['flat/recommended'],
  ...eslintLove
]

eslint-config-love/lib/index.js

......
......
......
const eslintRuleNames = [...(new utils_1.TSESLint.Linter()).getRules().keys()];
const namesOfEslintRulesForWhichWeAreUsingTsEquivalents = eslintRuleNames
    .filter(name => Object.hasOwn(rules, `@typescript-eslint/${name}`));
const config = {
    languageOptions: {
        parser: typescript_eslint_1.parser,
        parserOptions: {
            project: true
        }
    },
    plugins: {
        '@typescript-eslint': typescript_eslint_1.plugin,
        import: importPlugin,
        n: nPlugin,
        promise: promisePlugin
    },
    rules: {
        ...Object.fromEntries(namesOfEslintRulesForWhichWeAreUsingTsEquivalents.map(name => [name, ['off']])),
        ...rules
    }
};
module.exports = config;
//# sourceMappingURL=index.js.map

[mightyiam]

Seems like in the usage example you provided eslintLove is behind the spread operator. But it's an object, not an array.

[TyIsI]

I also encountered this. With both yarn and pnpm.
Created a minimal reproduction with yarn v3.

https://github.com/TyIsI/eslint-config-love-flat-config-issue

tyisi@beast:~/workspace/fafo/eslint-config-test$ yarn eslint

Oops! Something went wrong! :(

ESLint: 9.3.0

Error: This method cannot be used with flat config. Add your entries directly into the config array.
    at assertEslintrcConfig (/home/tyisi/.yarn/berry/cache/eslint-npm-9.3.0-90fe77a320-10c0.zip/node_modules/eslint/lib/linter/linter.js:1256:15)
    at Linter.getRules (/home/tyisi/.yarn/berry/cache/eslint-npm-9.3.0-90fe77a320-10c0.zip/node_modules/eslint/lib/linter/linter.js:2185:9)
    at Object.<anonymous> (/home/tyisi/workspace/fafo/eslint-config-test/.yarn/__virtual__/eslint-config-love-virtual-11964449a1/4/.yarn/berry/cache/eslint-config-love-npm-48.0.0-fe763c971f-10c0.zip/node_modules/eslint-config-love/lib/index.js:418:61)
    at Module._compile (node:internal/modules/cjs/loader:1358:14)
    at Module._extensions..js (node:internal/modules/cjs/loader:1416:10)
    at require$$0.Module._extensions..js (/home/tyisi/workspace/fafo/eslint-config-test/.pnp.cjs:10067:33)
    at Module.load (node:internal/modules/cjs/loader:1208:32)
    at Module._load (node:internal/modules/cjs/loader:1024:12)
    at require$$0.Module._load (/home/tyisi/workspace/fafo/eslint-config-test/.pnp.cjs:9915:31)
    at cjsLoader (node:internal/modules/esm/translators:348:17)
tyisi@beast:~/workspace/fafo/eslint-config-test$ 

The main difference I see is that the eslint-config-love repo uses eslint 8.57.0 and that both @zN3utr4l and myself use 9.3.0.

I'll test to see downgrading makes a difference.

[TyIsI]

I can confirm that downgrading to eslint 8.57.0 works.

tyisi@beast:~/workspace/fafo/eslint-config-test$ yarn eslint src

/home/tyisi/workspace/fafo/eslint-config-test/src/test.ts
  3:8  error    Missing return type on function           @typescript-eslint/explicit-function-return-type
  6:8  warning  Unexpected var, use let or const instead  no-var

✖ 2 problems (1 error, 1 warning)
  0 errors and 1 warning potentially fixable with the `--fix` option.

tyisi@beast:~/workspace/fafo/eslint-config-test$ 

[TyIsI]

Downgrade confirmation is in the downgrade branch:

TyIsI/eslint-config-love-flat-config-issue@main...downgrade

[mightyiam]

Indeed this project is not tested with ESLInt 9 yet.

[TyIsI]

Took the liberty of linking back here from the issue.

Downgrading fixed it for me.