Configure import/extensions for ESM

Author: matejchalk

docs/javascript.md

@@ -191,7 +191,7 @@ Refer to [setup instructions in README](../README.md#🏗️-setup).
 |             [![@typescript-eslint](./icons/material/typescript.png)](https://typescript-eslint.io/)              | [prefer-function-type](https://typescript-eslint.io/rules/prefer-function-type)<br />Enforce using function types instead of interfaces with call signatures                                                                                                                                                                                             |                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                          |   🔧    |           |
 | [![functional](./icons/icons8/lambda.png)](https://github.com/eslint-functional/eslint-plugin-functional#readme) | [no-let](https://github.com/eslint-functional/eslint-plugin-functional/blob/v7.0.0/docs/rules/no-let.md)<br />Disallow mutable variables.                                                                                                                                                                                                                |                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                          |         |   🧪🚫    |
 | [![functional](./icons/icons8/lambda.png)](https://github.com/eslint-functional/eslint-plugin-functional#readme) | [no-loop-statements](https://github.com/eslint-functional/eslint-plugin-functional/blob/v7.0.0/docs/rules/no-loop-statements.md)<br />Disallow imperative loops.                                                                                                                                                                                         |                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                          |         |           |
-|         [![import](./icons/icons8/import.png)](https://github.com/import-js/eslint-plugin-import#readme)         | [extensions](https://github.com/import-js/eslint-plugin-import/blob/v2.31.0/docs/rules/extensions.md)<br />Ensure consistent use of file extension within the import path.                                                                                                                                                                               | <details><summary>never, json: always</summary><pre lang="json"><code>[&#13;  "never",&#13;  {&#13;    "json": "always"&#13;  }&#13;]</code></pre></details>                                                                                                                                                                                                                                                                                                                                                                                                             |         |           |
+|         [![import](./icons/icons8/import.png)](https://github.com/import-js/eslint-plugin-import#readme)         | [extensions](https://github.com/import-js/eslint-plugin-import/blob/v2.31.0/docs/rules/extensions.md)<br />Ensure consistent use of file extension within the import path.                                                                                                                                                                               | <details><summary>always, ignorePackages: tru...</summary><pre lang="json"><code>[&#13;  "always",&#13;  {&#13;    "ignorePackages": true,&#13;    "checkTypeImports": true&#13;  }&#13;]</code></pre></details>                                                                                                                                                                                                                                                                                                                                                         |         |           |
 |         [![import](./icons/icons8/import.png)](https://github.com/import-js/eslint-plugin-import#readme)         | [max-dependencies](https://github.com/import-js/eslint-plugin-import/blob/v2.31.0/docs/rules/max-dependencies.md)<br />Enforce the maximum number of dependencies a module can have.                                                                                                                                                                     | <details><summary>ignoreTypeImports: true</summary><pre lang="json"><code>{&#13;  "ignoreTypeImports": true&#13;}</code></pre></details>                                                                                                                                                                                                                                                                                                                                                                                                                                 |         |           |
 |         [![import](./icons/icons8/import.png)](https://github.com/import-js/eslint-plugin-import#readme)         | [no-anonymous-default-export](https://github.com/import-js/eslint-plugin-import/blob/v2.31.0/docs/rules/no-anonymous-default-export.md)<br />Forbid anonymous values as default exports.                                                                                                                                                                 |                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                          |         |           |
 |         [![import](./icons/icons8/import.png)](https://github.com/import-js/eslint-plugin-import#readme)         | [no-duplicates](https://github.com/import-js/eslint-plugin-import/blob/v2.31.0/docs/rules/no-duplicates.md)<br />Forbid repeated import of the same module in multiple places.                                                                                                                                                                           |                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                          |   🔧    |           |

eslint.config.js

@@ -7,7 +7,6 @@ import vitest from './src/configs/vitest.js';
 export default tseslint.config(...node, ...vitest, {
   rules: {
     '@typescript-eslint/no-magic-numbers': 'off',
-    'import/extensions': ['error', { js: 'always', json: 'never' }],
   },
   settings: {
     'import/resolver': {

src/configs/javascript.js

@@ -160,7 +160,11 @@ export default tseslint.config(
           '@typescript-eslint/no-shadow': 'warn',
 
           // https://github.com/import-js/eslint-plugin-import#rules
-          'import/extensions': ['warn', 'never', { json: 'always' }],
+          'import/extensions': [
+            'warn',
+            'always',
+            { ignorePackages: true, checkTypeImports: true },
+          ],
           'import/max-dependencies': ['warn', { ignoreTypeImports: true }],
           'import/no-absolute-path': 'error',
           'import/no-amd': 'error',