chore: migrate to ESLint flat config (#26583)

.eslintrc

@@ -1,224 +0,0 @@
-{
-  "$schema": "https://json.schemastore.org/eslintrc",
-  "ignorePatterns": [
-    "dist",
-    "public",
-    "node_modules",
-    "packages/schema/schema"
-  ],
-  "globals": {
-    "NodeJS": true,
-    "$fetch": true
-  },
-  "plugins": ["jsdoc", "import", "unicorn", "no-only-tests"],
-  "extends": [
-    "standard",
-    "plugin:jsdoc/recommended",
-    "@nuxt/eslint-config",
-    "plugin:import/typescript"
-  ],
-  "rules": {
-    // Imports should come first
-    "import/first": "error",
-    // Other import rules
-    "import/no-mutable-exports": "error",
-    // Allow unresolved imports
-    "import/no-unresolved": "off",
-    // Allow paren-less arrow functions only when there's no braces
-    "arrow-parens": ["error", "as-needed", { "requireForBlockBody": true }],
-    // Allow async-await
-    "generator-star-spacing": "off",
-    // Prefer const over let
-    "prefer-const": ["error", { "destructuring": "any", "ignoreReadBeforeAssign": false }],
-    // No single if in an "else" block
-    "no-lonely-if": "error",
-    // Force curly braces for control flow,
-    // including if blocks with a single statement
-    "curly": ["error", "all"
-    ],
-    // No async function without await
-    "require-await": "error",
-    // Force dot notation when possible
-    "dot-notation": "error",
-
-    "no-var": "error",
-    // Force object shorthand where possible
-    "object-shorthand": "error",
-    // No useless destructuring/importing/exporting renames
-    "no-useless-rename": "error",
-    /**********************/
-    /*   Unicorn Rules    */
-    /**********************/
-    // Pass error message when throwing errors
-    "unicorn/error-message": "error",
-    // Uppercase regex escapes
-    "unicorn/escape-case": "error",
-    // Array.isArray instead of instanceof
-    "unicorn/no-array-instanceof": "error",
-    // Prevent deprecated `new Buffer()`
-    "unicorn/no-new-buffer": "error",
-    // Keep regex literals safe!
-    "unicorn/no-unsafe-regex": "off",
-    // Lowercase number formatting for octal, hex, binary (0x12 instead of 0X12)
-    "unicorn/number-literal-case": "error",
-    // ** instead of Math.pow()
-    "unicorn/prefer-exponentiation-operator": "error",
-    // includes over indexOf when checking for existence
-    "unicorn/prefer-includes": "error",
-    // String methods startsWith/endsWith instead of more complicated stuff
-    "unicorn/prefer-starts-ends-with": "error",
-    // textContent instead of innerText
-    "unicorn/prefer-text-content": "error",
-    // Enforce throwing type error when throwing error while checking typeof
-    "unicorn/prefer-type-error": "error",
-    // Use new when throwing error
-    "unicorn/throw-new-error": "error",
-    "sort-imports": [
-      "error",
-      {
-        "ignoreDeclarationSort": true
-      }
-    ],
-    "no-only-tests/no-only-tests": "error",
-    "unicorn/prefer-node-protocol": "error",
-    "no-console": "warn",
-    "vue/one-component-per-file": "off",
-    "vue/require-default-prop": "off",
-
-    // Vue stylistic rules from `@antfu/eslint-config`
-    "vue/array-bracket-spacing": ["error", "never"],
-    "vue/arrow-spacing": ["error", { "after": true, "before": true }],
-    "vue/block-spacing": ["error", "always"],
-    "vue/block-tag-newline": [
-      "error",
-      {
-        "multiline": "always",
-        "singleline": "always"
-      }
-    ],
-    "vue/brace-style": ["error", "stroustrup", { "allowSingleLine": true }],
-    "vue/comma-dangle": ["error", "always-multiline"],
-    "vue/comma-spacing": ["error", { "after": true, "before": false }],
-    "vue/comma-style": ["error", "last"],
-    "vue/html-comment-content-spacing": [
-      "error",
-      "always",
-      {
-        "exceptions": ["-"]
-      }
-    ],
-    "vue/key-spacing": ["error", { "afterColon": true, "beforeColon": false }],
-    "vue/keyword-spacing": ["error", { "after": true, "before": true }],
-    "vue/object-curly-newline": "off",
-    "vue/object-curly-spacing": ["error", "always"],
-    "vue/object-property-newline": [
-      "error",
-      { "allowMultiplePropertiesPerLine": true }
-    ],
-    "vue/operator-linebreak": ["error", "before"],
-    "vue/padding-line-between-blocks": ["error", "always"],
-    "vue/quote-props": ["error", "consistent-as-needed"],
-    "vue/space-in-parens": ["error", "never"],
-    "vue/template-curly-spacing": "error",
-
-    "jsdoc/require-jsdoc": "off",
-    "jsdoc/require-param": "off",
-    "jsdoc/require-returns": "off",
-    "jsdoc/require-param-type": "off",
-    "import/order": [
-      "error",
-      {
-        "pathGroups": [
-          {
-            "pattern": "#vue-router",
-            "group": "external"
-          }
-        ]
-      }
-    ],
-    "import/no-restricted-paths": [
-      "error",
-      {
-        "zones": [
-          {
-            "from": "packages/nuxt/src/!(core)/**/*",
-            "target": "packages/nuxt/src/core",
-            "message": "core should not directly import from modules."
-          },
-          {
-            "from": "packages/nuxt/src/!(app)/**/*",
-            "target": "packages/nuxt/src/app",
-            "message": "app should not directly import from modules."
-          },
-          {
-            "from": "packages/nuxt/src/app/**/index.ts",
-            "target": "packages/nuxt/src",
-            "message": "should not import from barrel/index files"
-          },
-          {
-            "from": "packages/nitro",
-            "target": "packages/!(nitro)/**/*",
-            "message": "nitro should not directly import other packages."
-          }
-        ]
-      }
-    ],
-    "@typescript-eslint/consistent-type-imports": [
-      "error",
-      {
-        "disallowTypeAnnotations": false
-      }
-    ],
-    "@typescript-eslint/ban-ts-comment": [
-      "error",
-      {
-        "ts-expect-error": "allow-with-description",
-        "ts-ignore": true
-      }
-    ],
-    "@typescript-eslint/prefer-ts-expect-error": "error",
-    "@typescript-eslint/no-unused-vars": [
-      "error",
-      {
-        "argsIgnorePattern": "^_",
-        "varsIgnorePattern": "^_",
-        "ignoreRestSiblings": true
-      }
-    ],
-    "jsdoc/check-tag-names": [
-      "error",
-      {
-        "definedTags": ["__NO_SIDE_EFFECTS__"]
-      }
-    ]
-  },
-  "overrides": [
-    {
-      "files": ["packages/schema/**"],
-      "rules": {
-        "jsdoc/valid-types": "off",
-        "jsdoc/check-tag-names": [
-          "error",
-          {
-            "definedTags": ["experimental"]
-          }
-        ]
-      }
-    },
-    {
-      "files": ["packages/nuxt/src/app/**", "test/**", "**/runtime/**"],
-      "rules": {
-        "no-console": "off"
-      }
-    }
-  ],
-  "settings": {
-    "jsdoc": {
-      "ignoreInternal": true,
-      "tagNamePreference": {
-        "warning": "warning",
-        "note": "note"
-      }
-    }
-  }
-}

eslint.config.mjs

@@ -0,0 +1,280 @@
+// Configs
+// import standard from "eslint-config-standard"
+// import nuxt from '@nuxt/eslint-config'
+
+// Plugins
+import path from 'node:path'
+import { fileURLToPath } from 'node:url'
+import jsdoc from 'eslint-plugin-jsdoc'
+import esImport from 'eslint-plugin-import'
+import unicorn from 'eslint-plugin-unicorn'
+import noOnlyTests from 'eslint-plugin-no-only-tests'
+
+/**
+ * eslintrc compatibility
+ * @see https://eslint.org/docs/latest/use/configure/migration-guide#using-eslintrc-configs-in-flat-config
+ * @see https://github.com/eslint/eslintrc#usage-esm
+ */
+import { FlatCompat } from '@eslint/eslintrc'
+import js from '@eslint/js'
+
+const __filename = fileURLToPath(import.meta.url)
+const __dirname = path.dirname(__filename)
+
+const compat = new FlatCompat({
+  baseDirectory: __dirname,
+  recommendedConfig: js.configs.recommended
+})
+
+// TODO: Type definition?
+export default [
+  {
+    ignores: [
+      '**/dist/**',
+      '**/.nuxt/**',
+      '**/.nuxt-*/**',
+      '**/.output/**',
+      '**/.output-*/**',
+      '**/public/**',
+      '**/node_modules/**',
+      'packages/schema/schema',
+
+      // TODO: remove when fully migrated to flat config
+      '**/*.d.mts'
+    ]
+  },
+  // standard,
+  ...compat.extends('eslint-config-standard'),
+  jsdoc.configs['flat/recommended'],
+  // nuxt,
+  ...compat.extends('@nuxt/eslint-config'),
+  esImport.configs.typescript,
+  {
+    rules: {
+      'import/export': 'off'
+    }
+  },
+  {
+    files: ['**/*.vue', '**/*.ts', '**/*.mts', '**/*.js', '**/*.cjs', '**/*.mjs'],
+    languageOptions: {
+      globals: {
+        NodeJS: 'readonly',
+        $fetch: 'readonly'
+      }
+    },
+    plugins: {
+      jsdoc,
+      import: esImport,
+      unicorn,
+      'no-only-tests': noOnlyTests
+    },
+    rules: {
+      // Imports should come first
+      'import/first': 'error',
+      // Other import rules
+      'import/no-mutable-exports': 'error',
+      // Allow unresolved imports
+      'import/no-unresolved': 'off',
+      // Allow paren-less arrow functions only when there's no braces
+      'arrow-parens': ['error', 'as-needed', { requireForBlockBody: true }],
+      // Allow async-await
+      'generator-star-spacing': 'off',
+      // Prefer const over let
+      'prefer-const': ['error', { destructuring: 'any', ignoreReadBeforeAssign: false }],
+      // No single if in an "else" block
+      'no-lonely-if': 'error',
+      // Force curly braces for control flow,
+      // including if blocks with a single statement
+      curly: ['error', 'all'],
+      // No async function without await
+      'require-await': 'error',
+      // Force dot notation when possible
+      'dot-notation': 'error',
+
+      'no-var': 'error',
+      // Force object shorthand where possible
+      'object-shorthand': 'error',
+      // No useless destructuring/importing/exporting renames
+      'no-useless-rename': 'error',
+      /**********************/
+      /*   Unicorn Rules    */
+      /**********************/
+      // Pass error message when throwing errors
+      'unicorn/error-message': 'error',
+      // Uppercase regex escapes
+      'unicorn/escape-case': 'error',
+      // Array.isArray instead of instanceof
+      'unicorn/no-array-instanceof': 'error',
+      // Prevent deprecated `new Buffer()`
+      'unicorn/no-new-buffer': 'error',
+      // Keep regex literals safe!
+      'unicorn/no-unsafe-regex': 'off',
+      // Lowercase number formatting for octal, hex, binary (0x12 instead of 0X12)
+      'unicorn/number-literal-case': 'error',
+      // ** instead of Math.pow()
+      'unicorn/prefer-exponentiation-operator': 'error',
+      // includes over indexOf when checking for existence
+      'unicorn/prefer-includes': 'error',
+      // String methods startsWith/endsWith instead of more complicated stuff
+      'unicorn/prefer-starts-ends-with': 'error',
+      // textContent instead of innerText
+      'unicorn/prefer-text-content': 'error',
+      // Enforce throwing type error when throwing error while checking typeof
+      'unicorn/prefer-type-error': 'error',
+      // Use new when throwing error
+      'unicorn/throw-new-error': 'error',
+      'sort-imports': [
+        'error',
+        {
+          ignoreDeclarationSort: true
+        }
+      ],
+      'no-only-tests/no-only-tests': 'error',
+      'unicorn/prefer-node-protocol': 'error',
+      'no-console': ['warn', { allow: ['warn', 'error', 'debug'] }],
+      'vue/one-component-per-file': 'off',
+      'vue/require-default-prop': 'off',
+
+      // Vue stylistic rules from `@antfu/eslint-config`
+      'vue/array-bracket-spacing': ['error', 'never'],
+      'vue/arrow-spacing': ['error', { after: true, before: true }],
+      'vue/block-spacing': ['error', 'always'],
+      'vue/block-tag-newline': [
+        'error',
+        {
+          multiline: 'always',
+          singleline: 'always'
+        }
+      ],
+      'vue/brace-style': ['error', 'stroustrup', { allowSingleLine: true }],
+      'vue/comma-dangle': ['error', 'always-multiline'],
+      'vue/comma-spacing': ['error', { after: true, before: false }],
+      'vue/comma-style': ['error', 'last'],
+      'vue/html-comment-content-spacing': [
+        'error',
+        'always',
+        {
+          exceptions: ['-']
+        }
+      ],
+      'vue/key-spacing': ['error', { afterColon: true, beforeColon: false }],
+      'vue/keyword-spacing': ['error', { after: true, before: true }],
+      'vue/object-curly-newline': 'off',
+      'vue/object-curly-spacing': ['error', 'always'],
+      'vue/object-property-newline': [
+        'error',
+        { allowMultiplePropertiesPerLine: true }
+      ],
+      'vue/operator-linebreak': ['error', 'before'],
+      'vue/padding-line-between-blocks': ['error', 'always'],
+      'vue/quote-props': ['error', 'consistent-as-needed'],
+      'vue/space-in-parens': ['error', 'never'],
+      'vue/template-curly-spacing': 'error',
+
+      'jsdoc/require-jsdoc': 'off',
+      'jsdoc/require-param': 'off',
+      'jsdoc/require-returns': 'off',
+      'jsdoc/require-param-type': 'off',
+      'import/order': [
+        'error',
+        {
+          pathGroups: [
+            {
+              pattern: '#vue-router',
+              group: 'external'
+            }
+          ]
+        }
+      ],
+      'import/no-restricted-paths': [
+        'error',
+        {
+          zones: [
+            {
+              from: 'packages/nuxt/src/!(core)/**/*',
+              target: 'packages/nuxt/src/core',
+              message: 'core should not directly import from modules.'
+            },
+            {
+              from: 'packages/nuxt/src/!(app)/**/*',
+              target: 'packages/nuxt/src/app',
+              message: 'app should not directly import from modules.'
+            },
+            {
+              from: 'packages/nuxt/src/app/**/index.ts',
+              target: 'packages/nuxt/src',
+              message: 'should not import from barrel/index files'
+            },
+            {
+              from: 'packages/nitro',
+              target: 'packages/!(nitro)/**/*',
+              message: 'nitro should not directly import other packages.'
+            }
+          ]
+        }
+      ],
+      '@typescript-eslint/consistent-type-imports': [
+        'error',
+        {
+          disallowTypeAnnotations: false
+        }
+      ],
+      '@typescript-eslint/ban-ts-comment': [
+        'error',
+        {
+          'ts-expect-error': 'allow-with-description',
+          'ts-ignore': true
+        }
+      ],
+      '@typescript-eslint/prefer-ts-expect-error': 'error',
+      '@typescript-eslint/no-unused-vars': [
+        'error',
+        {
+          argsIgnorePattern: '^_',
+          varsIgnorePattern: '^_',
+          ignoreRestSiblings: true
+        }
+      ],
+      'jsdoc/check-tag-names': [
+        'error',
+        {
+          definedTags: ['__NO_SIDE_EFFECTS__']
+        }
+      ]
+    },
+    settings: {
+      jsdoc: {
+        ignoreInternal: true,
+        tagNamePreference: {
+          warning: 'warning',
+          note: 'note'
+        }
+      }
+    }
+  },
+  {
+    files: ['packages/schema/**'],
+    rules: {
+      'jsdoc/valid-types': 'off',
+      'jsdoc/check-tag-names': [
+        'error',
+        {
+          definedTags: ['experimental']
+        }
+      ]
+    }
+  },
+  {
+    files: ['packages/nuxt/src/app/**', 'test/**', '**/runtime/**', '**/*.test.ts'],
+    rules: {
+      'no-console': 'off'
+    }
+  },
+  {
+    files: ['test/fixtures/**'],
+    rules: {
+      '@typescript-eslint/no-unused-vars': 'off',
+      'vue/valid-v-for': 'off'
+    }
+  }
+]

package.json

@@ -13,8 +13,8 @@
     "cleanup": "rimraf 'packages/**/node_modules' 'playground/node_modules' 'node_modules'",
     "dev": "pnpm play",
     "dev:prepare": "pnpm --filter './packages/**' prepack --stub",
-    "lint": "eslint --ext .vue,.ts,.js,.mjs .",
-    "lint:fix": "eslint --ext .vue,.ts,.js,.mjs . --fix",
+    "lint": "eslint .",
+    "lint:fix": "eslint . --fix",
     "lint:docs": "markdownlint ./docs && case-police 'docs/**/*.md' *.md",
     "lint:docs:fix": "markdownlint ./docs --fix && case-police 'docs/**/*.md' *.md --fix",
     "lint:knip": "pnpx knip",
@@ -44,6 +44,8 @@
     "magic-string": "^0.30.8"
   },
   "devDependencies": {
+    "@eslint/eslintrc": "3.0.2",
+    "@eslint/js": "8.57.0",
     "@nuxt/eslint-config": "0.2.0",
     "@nuxt/kit": "workspace:*",
     "@nuxt/test-utils": "3.12.0",

packages/nuxt/config.cjs

@@ -1,3 +1,4 @@
+/* eslint-disable jsdoc/require-jsdoc */
 function defineNuxtConfig (config) {
   return config
 }

packages/nuxt/src/app/compat/capi.ts

@@ -1,3 +1,4 @@
+// eslint-disable-next-line import/export
 export * from 'vue'
 
 export const install = () => {}

packages/nuxt/src/components/tree-shake.ts

@@ -220,7 +220,7 @@ function isComponentNotCalledInSetup (codeAst: Node, name: string): string | voi
 
 /**
  * retrieve the component identifier being used on ssrRender callExpression
- * @param {CallExpression} ssrRenderNode - ssrRender callExpression
+ * @param ssrRenderNode - ssrRender callExpression
  */
 function getComponentName (ssrRenderNode: AcornNode<CallExpression>): string {
   const componentCall = ssrRenderNode.arguments[0] as Identifier | MemberExpression | CallExpression

packages/nuxt/types.d.mts

@@ -1,5 +1,4 @@
 /// <reference types="nitropack" />
-export * from './dist/index.js'
 
 import type { DefineNuxtConfig } from 'nuxt/config'
 import type { RuntimeConfig, SchemaDefinition } from 'nuxt/schema'
@@ -7,6 +6,8 @@ import type { H3Event } from 'h3'
 import type { NuxtIslandContext, NuxtIslandResponse, NuxtRenderHTMLContext } from './dist/app/types.js'
 import type { LogObject } from 'consola'
 
+export * from './dist/index.js'
+
 declare global {
   const defineNuxtConfig: DefineNuxtConfig
   const defineNuxtSchema: (schema: SchemaDefinition) => SchemaDefinition

pnpm-lock.yaml

@@ -19,6 +19,12 @@ importers:
 
   .:
     devDependencies:
+      '@eslint/eslintrc':
+        specifier: 3.0.2
+        version: 3.0.2
+      '@eslint/js':
+        specifier: 8.57.0
+        version: 8.57.0
       '@nuxt/eslint-config':
         specifier: 0.2.0
         version: 0.2.0(eslint@8.57.0)
@@ -1919,6 +1925,23 @@ packages:
     transitivePeerDependencies:
       - supports-color
 
+  /@eslint/eslintrc@3.0.2:
+    resolution: {integrity: sha512-wV19ZEGEMAC1eHgrS7UQPqsdEiCIbTKTasEfcXAigzoXICcqZSjBZEHlZwNVvKg6UBCjSlos84XiLqsRJnIcIg==}
+    engines: {node: ^18.18.0 || ^20.9.0 || >=21.1.0}
+    dependencies:
+      ajv: 6.12.6
+      debug: 4.3.4
+      espree: 10.0.1
+      globals: 14.0.0
+      ignore: 5.3.1
+      import-fresh: 3.3.0
+      js-yaml: 4.1.0
+      minimatch: 3.1.2
+      strip-json-comments: 3.1.1
+    transitivePeerDependencies:
+      - supports-color
+    dev: true
+
   /@eslint/js@8.57.0:
     resolution: {integrity: sha512-Ys+3g2TaW7gADOJzPt83SJtCDhMjndcDMFVQ/Tj9iA1BfJzFKD9mAUXT3OenpuPHbI6P/myECxRJrofUsDx/5g==}
     engines: {node: ^12.22.0 || ^14.17.0 || >=16.0.0}
@@ -6145,6 +6168,11 @@ packages:
     resolution: {integrity: sha512-wpc+LXeiyiisxPlEkUzU6svyS1frIO3Mgxj1fdy7Pm8Ygzguax2N3Fa/D/ag1WqbOprdI+uY6wMUl8/a2G+iag==}
     engines: {node: ^12.22.0 || ^14.17.0 || >=16.0.0}
 
+  /eslint-visitor-keys@4.0.0:
+    resolution: {integrity: sha512-OtIRv/2GyiF6o/d8K7MYKKbXrOUBIK6SfkIRM4Z0dY3w+LiQ0vy3F57m0Z71bjbyeiWFiHJ8brqnmE6H6/jEuw==}
+    engines: {node: ^18.18.0 || ^20.9.0 || >=21.1.0}
+    dev: true
+
   /eslint@8.57.0:
     resolution: {integrity: sha512-dZ6+mexnaTIbSBZWgou51U6OmzIhYM2VcNdtiTtI7qPNZm35Akpr0f6vtw3w1Kmn5PYo+tZVfh13WrhpS6oLqQ==}
     engines: {node: ^12.22.0 || ^14.17.0 || >=16.0.0}
@@ -6191,6 +6219,15 @@ packages:
     transitivePeerDependencies:
       - supports-color
 
+  /espree@10.0.1:
+    resolution: {integrity: sha512-MWkrWZbJsL2UwnjxTX3gG8FneachS/Mwg7tdGXce011sJd5b0JG54vat5KHnfSBODZ3Wvzd2WnjxyzsRoVv+ww==}
+    engines: {node: ^18.18.0 || ^20.9.0 || >=21.1.0}
+    dependencies:
+      acorn: 8.11.3
+      acorn-jsx: 5.3.2(acorn@8.11.3)
+      eslint-visitor-keys: 4.0.0
+    dev: true
+
   /espree@9.6.1:
     resolution: {integrity: sha512-oruZaFkjorTpF32kDSI5/75ViwGeZginGGy2NoOSg3Q9bnwlnmDm4HLnkl0RE3n+njDXR037aY1+x58Z/zFdwQ==}
     engines: {node: ^12.22.0 || ^14.17.0 || >=16.0.0}
@@ -6702,6 +6739,11 @@ packages:
     dependencies:
       type-fest: 0.20.2
 
+  /globals@14.0.0:
+    resolution: {integrity: sha512-oahGvuMGQlPw/ivIYBjVSrWAfWLBeku5tpPE2fOPLi+WHffIWbuh2tCjhyQhTBPMf5E9jDEH4FOmTYgYwbKwtQ==}
+    engines: {node: '>=18'}
+    dev: true
+
   /globalthis@1.0.3:
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     engines: {node: '>= 0.4'}