If your JavaScript is a mess, frameworks can only do so much to help. No matter what framework, "compiles-to-JS" language, or library you use, bugs and performance concerns will always be an issue if the underlying quality of your JavaScript is poor. With this hands-on guide, you'll learn how to test and refactor your existing code to help reduce complexity, improve readability, and gain confidence in the codebase

What is refactoring? -- Which JavaScript are you using? -- Testing -- Testing in action -- Basic refactoring goals -- Refactoring simple structures -- Refactoring functions and objects -- Refactoring within a hierarchy -- Refactoring to OOP patterns -- Asynchronous refactoring -- Functional refactoring -- Conclusion