Jun 22, 2024 · Jun 11, 2024 · Jun 13, 2024 · Jun 14, 2024 · Jun 14, 2024 · Jun 14, 2024
diff --git a/.cspell.json b/.cspell.json
    "esquery",
    "esrecurse",
    "estree",
    "extrafileextensions",
    "falsiness",
    "globby",
    "IDE's",
    "preact",
    "Premade",
    "prettier's",
    "projectservice",
    "quasis",
    "Quickstart",
    "recurse",
diff --git a/docs/packages/Parser.mdx b/docs/packages/Parser.mdx
 The default extensions are `['.js', '.mjs', '.cjs', '.jsx', '.ts', '.mts', '.cts', '.tsx']`.
 Add extensions starting with `.`, followed by the file extension. E.g. for a `.vue` file use `"extraFileExtensions": [".vue"]`.

 :::note
 See [Changes to `extraFileExtensions` with `projectService`](../troubleshooting/Performance.mdx#changes-to-extrafileextensions-with-projectservice) to avoid performance issues.
 :::

 ### `jsDocParsingMode`

 > Default if `parserOptions.project` is set, then `'all'`, otherwise `'none'`
diff --git a/docs/packages/TypeScript_ESTree.mdx b/docs/packages/TypeScript_ESTree.mdx
  /**
   * When `project` is provided, this controls the non-standard file extensions which will be parsed.
   * It accepts an array of file extensions, each preceded by a `.`.
   *
   * NOTE: When used with {@link projectService}, full project reloads may occur.
   */
  extraFileExtensions?: string[];

diff --git a/docs/troubleshooting/FAQ.mdx b/docs/troubleshooting/FAQ.mdx

 You can use `parserOptions.extraFileExtensions` to specify an array of non-TypeScript extensions to allow, for example:

 :::note
 See [Changes to `extraFileExtensions` with `projectService`](../troubleshooting/Performance.mdx#changes-to-extrafileextensions-with-projectservice) to avoid performance issues.
 :::

 <Tabs groupId="eslint-config">
 <TabItem value="Flat Config">

diff --git a/docs/troubleshooting/Performance.mdx b/docs/troubleshooting/Performance.mdx

 See [Glob pattern in parser's option "project" slows down linting](https://github.com/typescript-eslint/typescript-eslint/issues/2611) for more details.

 ## Changes to `extraFileExtensions` with `projectService`

 Using a different [`extraFileExtensions`](../packages/Parser.mdx#extrafileextensions) between files in the same project with
 the [`projectService`](../packages/Parser.mdx#projectservice) option may cause performance degradations.
 For every file linted, we update the `projectService` whenever `extraFileExtensions` changes.
 This causes the underlying TypeScript server to perform a full project reload.

 <Tabs groupId="eslint-config">
 <TabItem value="Flat Config">

 ```js title="eslint.config.js"
 // @ts-check

 import tseslint from 'typescript-eslint';
 import vueParser from 'vue-eslint-parser';

 // Add this line
 const extraFileExtensions = ['.vue'];
 export default [
  {
    files: ['*.ts'],
    languageOptions: {
      parser: tseslint.parser,
      parserOptions: {
        projectService: true,
        // Add this line
        extraFileExtensions,
      },
    },
  },
  {
    files: ['*.vue'],
    languageOptions: {
      parser: vueParser,
      parserOptions: {
        projectService: true,
        parser: tseslint.parser,
        // Remove this line
        extraFileExtensions: ['.vue'],
        // Add this line
        extraFileExtensions,
      },
    },
  },
 ];
 ```

 </TabItem>
 <TabItem value="Legacy Config">

 ```js title=".eslintrc.js"
 // Add this line
 const extraFileExtensions = ['.vue'];
 module.exports = {
  files: ['*.ts'],
  parser: '@typescript-eslint/parser',
  parserOptions: {
    projectService: true,
    // Add this line
    extraFileExtensions,
  },
  overrides: [
    {
      files: ['*.vue'],
      parser: 'vue-eslint-parser',
      parserOptions: {
        parser: '@typescript-eslint/parser',
        projectService: true,
        // Remove this line
        extraFileExtensions: ['.vue'],
        // Add this line
        extraFileExtensions,
      },
    },
  ],
 };
 ```

 </TabItem>
 </Tabs>

 Project reloads can be observed using the [debug environment variable](../packages/typescript-estree/#debugging): `DEBUG='typescript-eslint:typescript-estree:*'`.

 ```
 typescript-estree:useProgramFromProjectService Updating extra file extensions: before=[]: after=[ '.vue' ]
 typescript-estree:tsserver:info reload projects.
 typescript-estree:useProgramFromProjectService Extra file extensions updated: [ '.vue' ]
 ...
 typescript-estree:useProgramFromProjectService Updating extra file extensions: before=[ '.vue' ]: after=[]
 typescript-estree:tsserver:info reload projects.
 typescript-estree:useProgramFromProjectService Extra file extensions updated: []
 ...
 typescript-estree:tsserver:info Scheduled: /path/to/tsconfig.src.json, Cancelled earlier one +0ms
 typescript-estree:tsserver:info Scheduled: *ensureProjectForOpenFiles*, Cancelled earlier one +0ms
 ...
 typescript-estree:useProgramFromProjectService Updating extra file extensions: before=[]: after=[ '.vue' ]
 typescript-estree:tsserver:info reload projects.
 typescript-estree:useProgramFromProjectService Extra file extensions updated: [ '.vue' ]
 ```

 ## The `indent` / `@typescript-eslint/indent` rules

 This rule helps ensure your codebase follows a consistent indentation pattern.
diff --git a/packages/typescript-estree/src/parser-options.ts b/packages/typescript-estree/src/parser-options.ts
  /**
   * When `project` is provided, this controls the non-standard file extensions which will be parsed.
   * It accepts an array of file extensions, each preceded by a `.`.
   *
   * NOTE: When used with {@link projectService}, full project reloads may occur.
   */
  extraFileExtensions?: string[];

diff --git a/packages/typescript-estree/src/useProgramFromProjectService.ts b/packages/typescript-estree/src/useProgramFromProjectService.ts
 import path from 'node:path';
 import util from 'node:util';

 import debug from 'debug';
 import { minimatch } from 'minimatch';
 import path from 'path';
 import { ScriptKind } from 'typescript';
 import * as ts from 'typescript';

 import { createProjectProgram } from './create-program/createProjectProgram';
 import type { ProjectServiceSettings } from './create-program/createProjectService';
  'typescript-eslint:typescript-estree:useProgramFromProjectService',
 );

 const serviceFileExtensions = new WeakMap<ts.server.ProjectService, string[]>();

 const updateExtraFileExtensions = (
  service: ts.server.ProjectService,
  extraFileExtensions: string[],
 ): void => {
  const currentServiceFileExtensions = serviceFileExtensions.get(service) ?? [];
  if (
    !util.isDeepStrictEqual(currentServiceFileExtensions, extraFileExtensions)
  ) {
    log(
      'Updating extra file extensions: before=%s: after=%s',
      currentServiceFileExtensions,
      extraFileExtensions,
    );
    service.setHostConfiguration({
      extraFileExtensions: extraFileExtensions.map(extension => ({
        extension,
        isMixedContent: false,
        scriptKind: ts.ScriptKind.Deferred,
      })),
    });
    serviceFileExtensions.set(service, extraFileExtensions);
    log('Extra file extensions updated: %o', extraFileExtensions);
  }
 };

 export function useProgramFromProjectService(
  {
    allowDefaultProject,
  hasFullTypeInformation: boolean,
  defaultProjectMatchedFiles: Set<string>,
 ): ASTAndDefiniteProgram | undefined {
  // NOTE: triggers a full project reload when changes are detected
  updateExtraFileExtensions(service, parseSettings.extraFileExtensions);

  // We don't canonicalize the filename because it caused a performance regression.
  // See https://github.com/typescript-eslint/typescript-eslint/issues/8519
  const filePathAbsolute = absolutify(parseSettings.filePath);
    filePathAbsolute,
  );

  if (parseSettings.extraFileExtensions.length) {
    service.setHostConfiguration({
      extraFileExtensions: parseSettings.extraFileExtensions.map(extension => ({
        extension,
        isMixedContent: false,
        scriptKind: ScriptKind.Deferred,
      })),
    });
  }

  const opened = service.openClientFile(
    filePathAbsolute,
    parseSettings.codeFullText,
Original file line number	Diff line number	Diff line change
Expand Up		@@ -88,6 +88,7 @@
		"esquery",
		"esrecurse",
		"estree",
		"extrafileextensions",
		"falsiness",
		"globby",
		"IDE's",
Expand DownExpand Up		@@ -120,6 +121,7 @@
		"preact",
		"Premade",
		"prettier's",
		"projectservice",
		"quasis",
		"Quickstart",
		"recurse",
Expand Down
Original file line number	Diff line number	Diff line change
Expand Up		@@ -152,6 +152,10 @@ This option allows you to provide one or more additional file extensions which s
		The default extensions are `['.js', '.mjs', '.cjs', '.jsx', '.ts', '.mts', '.cts', '.tsx']`.
		Add extensions starting with `.`, followed by the file extension. E.g. for a `.vue` file use `"extraFileExtensions": [".vue"]`.

		:::note
		See [Changes to `extraFileExtensions` with `projectService`](../troubleshooting/Performance.mdx#changes-to-extrafileextensions-with-projectservice) to avoid performance issues.
		:::

		### `jsDocParsingMode`

		> Default if `parserOptions.project` is set, then `'all'`, otherwise `'none'`
Expand Down
Original file line number	Diff line number	Diff line change
Expand Up		@@ -203,6 +203,8 @@ interface ParseAndGenerateServicesOptions extends ParseOptions {
		/**
		* When `project` is provided, this controls the non-standard file extensions which will be parsed.
		* It accepts an array of file extensions, each preceded by a `.`.
		*
		* NOTE: When used with {@link projectService}, full project reloads may occur.
		*/
		extraFileExtensions?: string[];

Expand Down
Original file line number	Diff line number	Diff line change
Expand Up		@@ -243,6 +243,10 @@ We don't recommend using `--cache`.

		You can use `parserOptions.extraFileExtensions` to specify an array of non-TypeScript extensions to allow, for example:

		:::note
		See [Changes to `extraFileExtensions` with `projectService`](../troubleshooting/Performance.mdx#changes-to-extrafileextensions-with-projectservice) to avoid performance issues.
		:::

		<Tabs groupId="eslint-config">
		<TabItem value="Flat Config">

Expand Down
Original file line number	Diff line number	Diff line change
Expand Up		@@ -79,6 +79,106 @@ module.exports = {

		See [Glob pattern in parser's option "project" slows down linting](https://github.com/typescript-eslint/typescript-eslint/issues/2611) for more details.

		## Changes to `extraFileExtensions` with `projectService`

		Using a different [`extraFileExtensions`](../packages/Parser.mdx#extrafileextensions) between files in the same project with
		the [`projectService`](../packages/Parser.mdx#projectservice) option may cause performance degradations.
		For every file linted, we update the `projectService` whenever `extraFileExtensions` changes.
		This causes the underlying TypeScript server to perform a full project reload.

		<Tabs groupId="eslint-config">
higherorderfunctor marked this conversation as resolved. Show resolvedHide resolved
		<TabItem value="Flat Config">

		```js title="eslint.config.js"
		// @ts-check

		import tseslint from 'typescript-eslint';
		import vueParser from 'vue-eslint-parser';

		// Add this line
		const extraFileExtensions = ['.vue'];
		export default [
		{
		files: ['*.ts'],
		languageOptions: {
		parser: tseslint.parser,
		parserOptions: {
		projectService: true,
		// Add this line
		extraFileExtensions,
		},
		},
		},
		{
		files: ['*.vue'],
		languageOptions: {
		parser: vueParser,
		parserOptions: {
		projectService: true,
		parser: tseslint.parser,
		// Remove this line
		extraFileExtensions: ['.vue'],
		// Add this line
		extraFileExtensions,
		},
		},
		},
		];
		```

		</TabItem>
		<TabItem value="Legacy Config">

		```js title=".eslintrc.js"
		// Add this line
		const extraFileExtensions = ['.vue'];
		module.exports = {
		files: ['*.ts'],
		parser: '@typescript-eslint/parser',
		parserOptions: {
		projectService: true,
		// Add this line
		extraFileExtensions,
		},
		overrides: [
		{
		files: ['*.vue'],
		parser: 'vue-eslint-parser',
		parserOptions: {
		parser: '@typescript-eslint/parser',
		projectService: true,
		// Remove this line
		extraFileExtensions: ['.vue'],
		// Add this line
		extraFileExtensions,
		},
		},
		],
		};
		```

		</TabItem>
		</Tabs>

		Project reloads can be observed using the [debug environment variable](../packages/typescript-estree/#debugging): `DEBUG='typescript-eslint:typescript-estree:*'`.

		```
		typescript-estree:useProgramFromProjectService Updating extra file extensions: before=[]: after=[ '.vue' ]
		typescript-estree:tsserver:info reload projects.
		typescript-estree:useProgramFromProjectService Extra file extensions updated: [ '.vue' ]
		...
		typescript-estree:useProgramFromProjectService Updating extra file extensions: before=[ '.vue' ]: after=[]
		typescript-estree:tsserver:info reload projects.
		typescript-estree:useProgramFromProjectService Extra file extensions updated: []
		...
		typescript-estree:tsserver:info Scheduled: /path/to/tsconfig.src.json, Cancelled earlier one +0ms
		typescript-estree:tsserver:info Scheduled: ensureProjectForOpenFiles, Cancelled earlier one +0ms
		...
		typescript-estree:useProgramFromProjectService Updating extra file extensions: before=[]: after=[ '.vue' ]
		typescript-estree:tsserver:info reload projects.
		typescript-estree:useProgramFromProjectService Extra file extensions updated: [ '.vue' ]
		```

		## The `indent` / `@typescript-eslint/indent` rules

		This rule helps ensure your codebase follows a consistent indentation pattern.
Expand Down
Original file line number	Diff line number	Diff line change
Expand Up		@@ -151,6 +151,8 @@ interface ParseAndGenerateServicesOptions extends ParseOptions {
		/**
		* When `project` is provided, this controls the non-standard file extensions which will be parsed.
		* It accepts an array of file extensions, each preceded by a `.`.
		*
		* NOTE: When used with {@link projectService}, full project reloads may occur.
		*/
		extraFileExtensions?: string[];

Expand Down
Original file line number	Diff line number	Diff line change
		@@ -1,7 +1,9 @@
		import path from 'node:path';
		import util from 'node:util';

		import debug from 'debug';
		import { minimatch } from 'minimatch';
		import path from 'path';
		import { ScriptKind } from 'typescript';
		import * as ts from 'typescript';

		import { createProjectProgram } from './create-program/createProjectProgram';
		import type { ProjectServiceSettings } from './create-program/createProjectService';
Expand All		@@ -13,6 +15,33 @@ const log = debug(
		'typescript-eslint:typescript-estree:useProgramFromProjectService',
		);

		const serviceFileExtensions = new WeakMap<ts.server.ProjectService, string[]>();

		const updateExtraFileExtensions = (
		service: ts.server.ProjectService,
		extraFileExtensions: string[],
		): void => {
		const currentServiceFileExtensions = serviceFileExtensions.get(service) ?? [];
		if (
		!util.isDeepStrictEqual(currentServiceFileExtensions, extraFileExtensions)
		) {
		log(
		'Updating extra file extensions: before=%s: after=%s',
		currentServiceFileExtensions,
		extraFileExtensions,
		);
		service.setHostConfiguration({
		extraFileExtensions: extraFileExtensions.map(extension => ({
		extension,
		isMixedContent: false,
		scriptKind: ts.ScriptKind.Deferred,
		})),
		});
		serviceFileExtensions.set(service, extraFileExtensions);
		log('Extra file extensions updated: %o', extraFileExtensions);
		}
		};

		export function useProgramFromProjectService(
		{
		allowDefaultProject,
Expand All		@@ -23,6 +52,9 @@ export function useProgramFromProjectService(
		hasFullTypeInformation: boolean,
		defaultProjectMatchedFiles: Set<string>,
		): ASTAndDefiniteProgram \| undefined {
		// NOTE: triggers a full project reload when changes are detected
		updateExtraFileExtensions(service, parseSettings.extraFileExtensions);

		// We don't canonicalize the filename because it caused a performance regression.
		// See https://github.com/typescript-eslint/typescript-eslint/issues/8519
		const filePathAbsolute = absolutify(parseSettings.filePath);
Expand All		@@ -32,16 +64,6 @@ export function useProgramFromProjectService(
		filePathAbsolute,
		);

		if (parseSettings.extraFileExtensions.length) {
		service.setHostConfiguration({
		extraFileExtensions: parseSettings.extraFileExtensions.map(extension => ({
		extension,
		isMixedContent: false,
		scriptKind: ScriptKind.Deferred,
		})),
		});
		}

		const opened = service.openClientFile(
		filePathAbsolute,
		parseSettings.codeFullText,
Expand Down