Duplicate code detection: Tools you can use

I am looking out for a software that identifies duplicate/redundant Javascript code. I found one such开发者_StackOverflow tool named CloneDR, but don't know how good it is .

I was looking out for similar open source tools . Please guide .

I used PMD's Copy/Paste Detector (CPD) last year on a project. There was some code for EcmascriptLanguage support but I recall having to update GUI.java and recompile the project to get it to work.

If you use ruby (or even have it on your system) you may want to try flay-js (flay plugin)

It may be worth checking out the coverage section in Google Chrome, relatively new feature: https://developers.google.com/web/updates/2017/04/devtools-release-notes#coverage

Find unused CSS and JS code with the new Coverage tab. When you load or run a page, the tab tells you how much code was used, versus how much was loaded. You can reduce the size of your pages by only shipping the code that you need.