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React component names mangling

See original GitHub issue

Is this a bug report?

Yes. We aren’t able to make automation testing.

Did you try recovering your dependencies?



  1. node -v: 9.4.0
  2. npm -v: 5.6.0
  3. yarn --version (if you use Yarn): 1.3.2
  4. npm ls react-scripts (if you haven’t ejected): react-scripts-ts@2.13.0

Then, specify:

  1. Operating system: Windows 10
  2. Browser and version (if relevant):

Steps to Reproduce

  1. create-react-app
  2. yarn build
  3. Open in browser → React DevTools

Expected Behavior

We would like to see unminified component’s class names for our staging environment to make end-to-end automated testing. We use these names in our test cases, so we don’t want to see them mangled.

Actual Behavior

Class names are mangled.


It’s easy to fix by adding options to disable mangling in

new webpack.optimize.UglifyJsPlugin({
	// ...
	mangle: {
		keep_classnames: true,
		keep_fnames: true
	// ...

Maybe adding the option to .env file is good way here?

Issue Analytics

  • State:closed
  • Created 6 years ago
  • Reactions:3
  • Comments:12 (4 by maintainers)

github_iconTop GitHub Comments

gaearoncommented, Oct 4, 2018

One thing you can do is to explicitly give some components displayName. Minifier won’t remove it.

function Stuff() {}
Stuff.displayName = 'Stuff'

Giving it to every component is overkill and will bloat your bundle. But if you strategically pick a few dozen components (depending on your product size) I think it will give you a good balance.

Timercommented, Mar 26, 2018

No, sorry. Giving these sort of configuration options are outside of our values. If you feel strongly about this, you’ll need to eject.

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