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docs: update examples to use defineConfig #20131

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11 changes: 7 additions & 4 deletions docs/src/extend/custom-parsers.md
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Original file line number Diff line number Diff line change
Expand Up @@ -129,16 +129,17 @@ Then add the custom parser to your ESLint configuration file with the `languageO
```js
// eslint.config.js

const { defineConfig } = require("eslint/config");
const myparser = require("eslint-parser-myparser");

module.exports = [
module.exports = defineConfig([
{
languageOptions: {
parser: myparser,
},
// ... rest of configuration
},
];
]);
```

When using legacy configuration, specify the `parser` property as a string:
Expand Down Expand Up @@ -183,13 +184,15 @@ Include the custom parser in an ESLint configuration file:

```js
// eslint.config.js
module.exports = [
const { defineConfig } = require("eslint/config");

module.exports = defineConfig([
{
languageOptions: {
parser: require("./path/to/awesome-custom-parser"),
},
},
];
]);
```

Or if using legacy configuration:
Expand Down
73 changes: 45 additions & 28 deletions docs/src/use/configure/migration-guide.md
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Original file line number Diff line number Diff line change
Expand Up @@ -80,9 +80,10 @@ In flat config, you would do the same thing like this:
```javascript
// eslint.config.js

import { defineConfig } from "eslint/config";
import jsdoc from "eslint-plugin-jsdoc";

export default [
export default defineConfig([
{
files: ["**/*.js"],
plugins: {
Expand All @@ -93,7 +94,7 @@ export default [
"jsdoc/check-values": "error",
},
},
];
]);
```

::: tip
Expand Down Expand Up @@ -123,17 +124,18 @@ In flat config, you would do the same thing like this:
```javascript
// eslint.config.js

import { defineConfig } from "eslint/config";
import babelParser from "@babel/eslint-parser";

export default [
export default defineConfig([
{
// ...other config
languageOptions: {
parser: babelParser,
},
// ...other config
},
];
]);
```

### Processors
Expand Down Expand Up @@ -187,9 +189,10 @@ In flat config, the following are all valid ways to express the same:

```javascript
// eslint.config.js
import { defineConfig } from "eslint/config";
import somePlugin from "eslint-plugin-someplugin";

export default [
export default defineConfig([
{
plugins: { somePlugin },
processor: "somePlugin/someProcessor",
Expand All @@ -203,7 +206,7 @@ export default [
// We don't need the plugin to be present in the config to use the processor directly
processor: somePlugin.processors.someProcessor,
},
];
]);
```

Note that because the `.md` processor is _not_ automatically added by flat config, you also need to specify an extra configuration element:
Expand Down Expand Up @@ -265,9 +268,10 @@ For flat config, here is a configuration with the default glob pattern:
```javascript
// eslint.config.js

import { defineConfig } from "eslint/config";
import js from "@eslint/js";

export default [
export default defineConfig([
js.configs.recommended, // Recommended config applied to all files
// Override the recommended config
{
Expand All @@ -277,17 +281,18 @@ export default [
},
// ...other configuration
},
];
]);
```

A flat config example configuration supporting multiple configs for different glob patterns:

```javascript
// eslint.config.js

import { defineConfig } from "eslint/config";
import js from "@eslint/js";

export default [
export default defineConfig([
js.configs.recommended, // Recommended config applied to all files
// File-pattern specific overrides
{
Expand All @@ -303,7 +308,7 @@ export default [
},
},
// ...other configurations
];
]);
```

### Configuring Language Options
Expand Down Expand Up @@ -338,9 +343,10 @@ Here's the same configuration in flat config:
```javascript
// eslint.config.js

import { defineConfig } from "eslint/config";
import globals from "globals";

export default [
export default defineConfig([
{
languageOptions: {
ecmaVersion: 2022,
Expand All @@ -353,7 +359,7 @@ export default [
},
// ...other config
},
];
]);
```

::: tip
Expand Down Expand Up @@ -402,9 +408,10 @@ Another option is to remove the comment from the file being linted and define th
```javascript
// eslint.config.js

import { defineConfig } from "eslint/config";
import globals from "globals";

export default [
export default defineConfig([
// ...other config
{
files: ["tests/**"],
Expand All @@ -414,7 +421,7 @@ export default [
},
},
},
];
]);
```

### Predefined and Shareable Configs
Expand Down Expand Up @@ -475,11 +482,12 @@ To use the same configs in flat config, you would do the following:
```javascript
// eslint.config.js

import { defineConfig } from "eslint/config";
import js from "@eslint/js";
import customConfig from "./custom-config.js";
import myConfig from "eslint-config-my-config";

export default [
export default defineConfig([
js.configs.recommended,
customConfig,
myConfig,
Expand All @@ -489,24 +497,25 @@ export default [
},
// ...other config
},
];
]);
```

Note that because you are just importing JavaScript modules, you can mutate the config objects before ESLint uses them. For example, you might want to have a certain config object only apply to your test files:

```javascript
// eslint.config.js

import { defineConfig } from "eslint/config";
import js from "@eslint/js";
import customTestConfig from "./custom-test-config.js";

export default [
export default defineConfig([
js.configs.recommended,
{
...customTestConfig,
files: ["**/*.test.js"],
},
];
]);
```

#### Using eslintrc Configs in Flat Config
Expand All @@ -522,6 +531,7 @@ You may find that there's a shareable config you rely on that hasn't yet been up
Then, import `FlatCompat` and create a new instance to convert an existing eslintrc config. For example, if the npm package `eslint-config-my-config` is in eslintrc format, you can write this:

```js
import { defineConfig } from "eslint/config";
import { FlatCompat } from "@eslint/eslintrc";
import path from "path";
import { fileURLToPath } from "url";
Expand All @@ -534,10 +544,10 @@ const compat = new FlatCompat({
baseDirectory: __dirname,
});

export default [
export default defineConfig([
// mimic ESLintRC-style extends
...compat.extends("eslint-config-my-config"),
];
]);
```
This example uses the `FlatCompat#extends()` method to insert the `eslint-config-my-config` into the flat config array.
Expand Down Expand Up @@ -572,13 +582,15 @@ module.exports = {
The equivalent ignore patterns in flat config look like this:
```javascript
export default [
import { defineConfig } from "eslint/config";
export default defineConfig([
// ...other config
{
// Note: there should be no other properties in this object
ignores: ["**/temp.js", "config/*"],
},
];
]);
```
In `.eslintignore`, `temp.js` ignores all files named `temp.js`, whereas in flat config, you need to specify this as `**/temp.js`. The pattern `temp.js` in flat config only ignores a file named `temp.js` in the same directory as the configuration file.
Expand Down Expand Up @@ -610,15 +622,17 @@ Here's the same options in flat config:
```javascript
// eslint.config.js

export default [
import { defineConfig } from "eslint/config";

export default defineConfig([
{
// ...other config
linterOptions: {
noInlineConfig: true,
reportUnusedDisableDirectives: "warn",
},
},
];
]);
```
### CLI Flag Changes
Expand All @@ -637,9 +651,10 @@ The `--rulesdir` flag was used to load additional rules from a specified directo
```js
// eslint.config.js
import { defineConfig } from "eslint/config";
import myRule from "./rules/my-rule.js";

export default [
export default defineConfig([
{
// define the plugin
plugins: {
Expand All @@ -655,7 +670,7 @@ export default [
"local/my-rule": ["error"],
},
},
];
]);
```
#### `--ext`
Expand All @@ -664,13 +679,15 @@ The `--ext` flag was used to specify additional file extensions ESLint should se
```js
// eslint.config.js
export default [
import { defineConfig } from "eslint/config";

export default defineConfig([
{
files: ["**/*.ts", "**/*.tsx"],

// any additional configuration for these file types here
},
];
]);
```
ESLint uses the `files` keys from the config file to determine which files should be linted.
Expand Down
15 changes: 10 additions & 5 deletions docs/src/use/core-concepts/glossary.md
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Expand Up @@ -33,13 +33,15 @@ Each config file exports a [config array](#config-array) containing [config obje
For example, this `eslint.config.js` file enables the `prefer-const` [rule](#rule) at the _error_ [severity](#severity):

```js
export default [
import { defineConfig } from "eslint/config";

export default defineConfig([
{
rules: {
"prefer-const": "error",
},
},
];
]);
```

See [Configuration Files](../configure/configuration-files) for more details.
Expand Down Expand Up @@ -242,7 +244,9 @@ When a [config object](#config-object) or [inline config](#inline-config-configu
The following [config file](#config-file-configuration-file) overrides `no-unused-expressions` from `"error"` to `"off"` in `*.test.js` files:

```js
export default [
import { defineConfig } from "eslint/config";

export default defineConfig([
{
rules: {
"no-unused-expressions": "error",
Expand All @@ -254,7 +258,7 @@ export default [
"no-unused-expressions": "off",
},
},
];
]);
```

The following [inline config](#inline-config-configuration-comment) sets `no-unused-expressions` to `"error"`:
Expand Down Expand Up @@ -346,10 +350,11 @@ Many plugins provide configs with names like _"recommended"_ that enable their s
For example, [`eslint-plugin-solid`](https://github.com/solidjs-community/eslint-plugin-solid) provides a shareable recommended config:

```js
import { defineConfig } from "eslint/config";
import js from "@eslint/js";
import solid from "eslint-plugin-solid/configs/recommended";

export default [js.configs.recommended, solid];
export default defineConfig([js.configs.recommended, solid]);
```

For information on shareable configs, see [Share Configurations](../../extend/shareable-configs).
Expand Down
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