JavaScript

JavaScript support

JavaScript files are marked with icon. JavaScript support in IntelliJ IDEA includes:

• Switching between JavaScript language versions:
  • ECMAScript 3
  • ECMAScript 5.1
  • JavaScript 1.8.5
  • ECMAScript 6
  • React JSX
  • Flow
• Full coding assistance:
  • Smart code completion for keywords, labels, variables, parameters, user-defined or built-in functions, and JavaScript namespaces.
  • Error and syntax highlighting.
  • Code formatting and folding.
  • Numerous code inspections and quick-fixes.
  • Support of the strict mode standard.
• Code Generation
  • Generating code stubs based on file templates during file creation.
  • Inserting, expanding, and generating JavaScript code blocks using live templates.
  • Creating various applications elements via JavaScript and AJAX intention actions.
  • Ability to create line and block comments (Ctrl+Slash/Ctrl+Shift+Slash).
  • Unwrapping and removing statements.
• Possibility to build and view type, method and call hierarchies.
• Refactoring, both JavaScript-specific and available for all the supported languages. See Refactoring Source Code and Extract Parameter in JavaScript.
• Numerous ways to navigate through the source code, among them Navigating with Structure Views, Show/Goto Implementation (Ctrl+Alt+B) from overridden method / subclassed class, etc.
• Advanced facilities for searching through the source code.
• Support of the JSDoc format and generating documentation comments.
• Viewing reference information:
  • Definitions, inline documentation, parameter hints.
  • JSDoc comments.
  • Lookup in external JavaScript libraries.

• Running and debugging.

  • Debugging JavaScript applications running on the built-in server or on an external server.
  • A dedicated Firefox Remote debug configuration for debugging JavaScript in Firefox.
  • A JavaScript-aware debugger that lets you execute applications step by step, evaluate expressions, examine related information and find runtime bugs.
  • Support for JavaScript breakpoints.
• Tight integration with related frameworks and technologies.
• Support for the JSON (JavaScript Object Notation) format:
  • A JSON file type template mapped to json file extension.
  • JSON code formatting and folding.

Developing an application that contains JavaScript: general overview

Developing an application that contains JavaScript, generally, includes performing the following steps:

1. Create a project to implement your application. On the first page of the New Project wizard, select Static Web.
2. On the JavaScript page of the Settings dialog box, choose the JavaScript language version that you are going to use in your project.
3. Install the project dependencies via the Node Package Manager by doing one of the following:
   • 1. Open the Settings / Preferences Dialog by pressing Ctrl+Alt+S or by choosing File | Settings for Windows and Linux or IntelliJ IDEA | Preferences for macOS, and click Node.js and NPM under Languages & Frameworks.
     2. On the Node.js and NPM page that opens, the Packages area shows all the Node.js-dependent packages that are currently installed on your computer, both at the global and at the project level. Click .
     3. In the Available Packages dialog box that opens, select the required package.
     4. Optionally specify the product version and click Install Package to start installation.
   • Right-click the package.json file in the editor or in the Project tool window and choose Run 'npm install' on the context menu.
   • Open the built-in Terminal (View | Tool Windows | Terminal) and run the npm install <required_package> commands.
   • Install the required packages on the Node.js and NPM page of the Settings / Preferences Dialog.

   For details, see NPM.

4. Populate the project. Use the following IntelliJ IDEA facilities, where applicable:
   • Coding assistance.
   • Code Generation.
   • Various types of navigation and search through the source code.
   • Viewing reference and generating documentation comments.
   • Look-up in external libraries.
5. Improve the quality and maintainability of your code using various types of refactorings, built-in code quality tools, and integration with other linters, see JavaScript Linters.
6. Run your application by opening its starting HTML page in the IntelliJ IDEA default browser.
7. Debug your application in the Google Chrome browser.

   The JavaScript debugging functionality is incorporated in IntelliJ IDEA, so just configure the debugger, whereupon you can start the debugging session and proceed as usual: set the breakpoints, step through them, stop and resume the program, and examine it when suspended.

In this section

• Angular
• AngularJS
• Bower
• Configuring JavaScript Libraries
• Creating JSDoc Comments
• Debugging JavaScript in Chrome
• Debugging JavaScript in Firefox
• Flow Type Checker
• Grunt
• Gulp
• Handlebars and Mustache
• JavaScript Linters
• JavaScript Documentation Look-Up
• Live Editing of HTML, CSS, and JavaScript
• Meteor
• Minifying JavaScript
• Module Dependency Diagrams
• React
• Change Signature in JavaScript
• Extract Parameter in JavaScript
• Extract Variable in JavaScript
• Running JavaScript in Browser
• PhoneGap/Cordova
• Refactoring JavaScript
• Spy-js
• Testing JavaScript
• Vue.js
• Viewing Actual HTML DOM