JS packer + minifier + reduce

Question

Is there any analyser/parser that will parse my code, take the code from libraries that i really use and need, reduce unnecessary library code and make finally a minified package?

For example if im using only $(smth).show() in jQuery then this reducer only take the code and dependencies responsible for show() and exactly this case of the selector and remove anything else

Thanks

Answer 1

A very popular tool for this is Webpack which in its newest release v4 has "tree-shaking" capabilities. It can remove unnecessary code. (and optionally minifies and reduces, creates sourcemaps and more). Another such bundler is RollupJS.

However

• your code (and the code in the libraries you are using) has to be written in a very specific way in order for treeshaking to work.
• webpack and rollup.js can take some time to learn and set-up
• they are nodejs based so you need to learn node concepts first