Removing dead code in prod builds about proptypes HOT 2 OPEN

Hi @mikestead - would something like this work?

if (typeof process!=='undefined' && process.env.NODE_ENV!=='production') {

} else {

}

FWIW, I have found that you have to add a tiny bit extra in DefinePlugin to get things removed:

new DefinePlugin({
  process: {},
  'process.env': {},
  'process.env.NODE_ENV': JSON.stringify('production')
})

from proptypes.

Thanks for the input and tip, if I add process and process.env to the define plugin with no changes to PropTypes lib I do indeed see a little more code removed, and from react-router as well as preact/preact-compat.

libs.e47828f.js   129 kB    1, 2  [emitted]  libs 

I guess that's for code that also checks the parent chain of process.env.NODE_ENV in a conditional.

You are also correct the following does seem to work, and without touching the DefinePlugin.

if (typeof process!=='undefined' && process.env.NODE_ENV!=='production') {

But we're obv not checking for env here. If I add that check code isn't stripped... unless I go make those additions to the DefinePlugin :)

For backwards compatibility I tried switching it to

if (typeof process!=='undefined' && process.env.NODE_ENV==='production') {

and inverting the if else blocks, but then the code wasn't stripped. I guess Uglify may only like stripping from the if block?

If I swap back and then add process and process.env to DefinePlugin I can use an OR

if (typeof process==='undefined' || !process.env || process.env.NODE_ENV!=='production') { // dev

Let me know what you want to do, if anything and I'm happy to open a pull request.

from proptypes.