Intern : Intern is a complete test system for JavaScript designed to help you write and run consistent, high-quality test cases for your JavaScript libraries a...
domsnitch : A passive reconnaissance tool inside the DOM (experimental)
Cypress : JavaScript End to End Testing Framework. Fast, easy and reliable testing for anything that runs in a browser.
tracing-framework : Rich tools for instrumenting, analyzing, and visualizing web apps.
Greasemonkey : Greasemonkey is a Firefox extension that allows you to customize the way webpages look and function.