JSHint : A JavaScript Code Quality Tool. JSHint is a tool that helps to detect errors and potential problems in your JavaScript code.
PhantomJS : PhantomJS is a headless WebKit with JavaScript API. It has fast and native support for various web standards: DOM handling, CSS selector, JSON, Canvas...
Enzyme : Enzyme is a JavaScript Testing utility for React that makes it easier to assert, manipulate, and traverse your React Components' output.
jscs is a code style checker. jscs can check cases, which are not implemented in jshint, but it does not duplicate jshint functionality, so you should use jscs and jshint together.