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 .

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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.

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

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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.