# @codemirror/lang-javascript [![NPM version](https://img.shields.io/npm/v/@codemirror/lang-javascript.svg)](https://www.npmjs.org/package/@codemirror/lang-javascript) [ [**WEBSITE**](https://codemirror.net/) | [**ISSUES**](https://github.com/codemirror/dev/issues) | [**FORUM**](https://discuss.codemirror.net/c/next/) | [**CHANGELOG**](https://github.com/codemirror/lang-javascript/blob/main/CHANGELOG.md) ] This package implements JavaScript language support for the [CodeMirror](https://codemirror.net/) code editor. The [project page](https://codemirror.net/) has more information, a number of [examples](https://codemirror.net/examples/) and the [documentation](https://codemirror.net/docs/). This code is released under an [MIT license](https://github.com/codemirror/lang-javascript/tree/main/LICENSE). We aim to be an inclusive, welcoming community. To make that explicit, we have a [code of conduct](http://contributor-covenant.org/version/1/1/0/) that applies to communication around the project. ## Usage ```javascript import {EditorView, basicSetup} from "codemirror" import {javascript} from "@codemirror/lang-javascript" const view = new EditorView({ parent: document.body, doc: `console.log("Hello world")`, extensions: [basicSetup, javascript()] }) ``` ## API Reference
javascript(config⁠?: {jsx⁠?: boolean, typescript⁠?: boolean} = {}) → LanguageSupport

JavaScript support. Includes snippet and local variable completion.

javascriptLanguage: LRLanguage

A language provider based on the Lezer JavaScript parser, extended with highlighting and indentation information.

typescriptLanguage: LRLanguage

A language provider for TypeScript.

jsxLanguage: LRLanguage

Language provider for JSX.

tsxLanguage: LRLanguage

Language provider for JSX + TypeScript.

autoCloseTags: Extension

Extension that will automatically insert JSX close tags when a > or / is typed.

snippets: readonly Completion[]

A collection of JavaScript-related snippets.

typescriptSnippets: Completion[]

A collection of snippet completions for TypeScript. Includes the JavaScript snippets.

localCompletionSource(context: CompletionContext) → CompletionResult | null

Completion source that looks up locally defined names in JavaScript code.

completionPath(context: CompletionContext) → {path: readonly string[], name: string} | null

Helper function for defining JavaScript completion sources. It returns the completable name and object path for a completion context, or null if no name/property completion should happen at that position. For example, when completing after a.b.c it will return {path: ["a", "b"], name: "c"}. When completing after x it will return {path: [], name: "x"}. When not in a property or name, it will return null if context.explicit is false, and {path: [], name: ""} otherwise.

scopeCompletionSource(scope: any) → CompletionSource

Defines a completion source that completes from the given scope object (for example globalThis). Will enter properties of the object when completing properties on a directly-named path.

esLint(eslint: any, config⁠?: any) → fn(view: EditorView) → Diagnostic[]

Connects an ESLint linter to CodeMirror's lint integration. eslint should be an instance of the Linter class, and config an optional ESLint configuration. The return value of this function can be passed to linter to create a JavaScript linting extension.

Note that ESLint targets node, and is tricky to run in the browser. The eslint-linter-browserify package may help with that (see example).