yepnope.js : A Conditional Loader For Your Polyfills!
Enzyme : Enzyme is a JavaScript Testing utility for React that makes it easier to assert, manipulate, and traverse your React Components' output.
domsnitch : A passive reconnaissance tool inside the DOM (experimental)
JavaScript Code Style checker : 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...
Chai : Chai is a BDD / TDD assertion library for node and the browser that can be delightfully paired with any javascript testing framework.
Zombie.js is a lightweight framework for testing client-side JavaScript code in a simulated environment. No browser required.