.eslintrc.cjs

"use strict";

const cjsGlobals = ["__dirname", "__filename", "require", "module", "exports"];

const testFiles = [
  "packages/*/test/**/*.js",
  "codemods/*/test/**/*.js",
  "eslint/*/test/**/*.js",
];
const sourceFiles = exts => [
  `packages/*/src/**/*.{${exts}}`,
  `codemods/*/src/**/*.{${exts}}`,
  `eslint/*/src/**/*.{${exts}}`,
];

module.exports = {
  root: true,
  plugins: [
    "import",
    "node",
    "jest",
    "prettier",
    "@babel/development",
    "@babel/development-internal",
  ],
  extends: "@babel/internal",
  rules: {
    "prettier/prettier": "error",
    "import/no-extraneous-dependencies": "error",
  },
  env: {
    node: true,
  },
  overrides: [
    {
      files: ["**/*.ts"],
      parser: "@typescript-eslint/parser",
      plugins: ["@typescript-eslint"],
      rules: {
        "no-unused-vars": "off",
        "@typescript-eslint/no-unused-vars": "error",
        "no-dupe-class-members": "off",
        "@typescript-eslint/no-dupe-class-members": "error",
        "no-undef": "off",
        "no-redeclare": "off",
        "@typescript-eslint/ban-ts-comment": [
          "error",
          {
            "ts-ignore": { descriptionFormat: "^\\(Babel 7 vs Babel 8\\) .+$" },
          },
        ],
        "@typescript-eslint/consistent-type-imports": [
          "error",
          { disallowTypeAnnotations: false },
        ],
        "@typescript-eslint/no-use-before-define": [
          "error",
          {
            functions: false,
            classes: false,
            allowNamedExports: true,
          },
        ],
      },
    },
    {
      files: sourceFiles("js,ts,cjs,mjs"),
      rules: {
        "@babel/development/no-undefined-identifier": "error",
        "@babel/development/no-deprecated-clone": "error",
        "guard-for-in": "error",
        "import/extensions": ["error", { json: "always", cjs: "always" }],
      },
      globals: { PACKAGE_JSON: "readonly", USE_ESM: "readonly" },
    },
    {
      files: [
        ...testFiles,
        "packages/babel-helper-transform-fixture-test-runner/src/helpers.{ts,js}",
        "test/**/*.js",
      ],
      env: {
        jest: true,
      },
      extends: "plugin:jest/recommended",
      rules: {
        "jest/expect-expect": "off",
        "jest/no-identical-title": "off",
        "jest/no-standalone-expect": "off",
        "jest/no-test-callback": "off",
        "jest/valid-describe": "off",
        "import/extensions": ["error", "always"],
        "import/no-extraneous-dependencies": "off",
        "no-restricted-imports": ["error", { patterns: ["**/src/**"] }],
      },
    },
    {
      files: testFiles,
      rules: {
        "node/no-unsupported-features": [
          "error",
          { version: "12.17.0", ignores: ["modules"] },
        ],
        "@babel/development-internal/require-default-import-fallback": "error",
      },
    },
    {
      files: [...sourceFiles("js,ts,mjs"), ...testFiles, "test/**/*.js"],
      excludedFiles: [
        // @babel/register is the require() hook, so it will always be CJS-based
        "packages/babel-register/**/*.{js,ts}",
      ],
      rules: {
        "no-restricted-globals": ["error", ...cjsGlobals],
        "no-restricted-imports": [
          "error",
          {
            patterns: ["**/*.json"],
            paths: [
              {
                name: "semver",
                message:
                  "semver's named exports are not recognized by the Node.js ESM-CJS interop.",
                importNames: Object.keys(require("semver")).filter(
                  // We use it as a type import.
                  name => name !== "SemVer"
                ),
              },
            ],
          },
        ],
      },
    },
    {
      files: ["packages/babel-plugin-*/src/index.{js,ts}"],
      excludedFiles: ["packages/babel-plugin-transform-regenerator/**/*.js"],
      rules: {
        "@babel/development/plugin-name": "error",
        eqeqeq: ["error", "always", { null: "ignore" }],
      },
    },
    {
      files: ["packages/babel-helpers/src/helpers/**.js"],
      rules: {
        "no-var": "off",
        "comma-dangle": "off",
        "no-func-assign": "off",
        "import/no-extraneous-dependencies": "off",
      },
    },
    {
      files: ["packages/babel-traverse/scripts/**/*.js"],
      rules: {
        "import/no-extraneous-dependencies": [
          "error",
          { packageDir: "./packages/babel-traverse" },
        ],
      },
    },
    {
      files: ["eslint/babel-eslint-parser/src/**/*.js"],
      rules: {
        "no-restricted-imports": ["error", "@babel/core"],
      },
    },
    {
      files: ["packages/babel-plugin-transform-runtime/scripts/**/*.js"],
      rules: {
        "import/no-extraneous-dependencies": [
          "error",
          { packageDir: "./packages/babel-plugin-transform-runtime" },
        ],
      },
    },
    {
      files: ["packages/babel-preset-env/data/**/*.js"],
      rules: {
        "import/no-extraneous-dependencies": [
          "error",
          { packageDir: "./packages/babel-preset-env" },
        ],
      },
    },
    {
      files: ["scripts/**/*.js"],
      rules: {
        "import/no-extraneous-dependencies": ["error", { packageDir: "." }],
      },
    },
  ],
};