Add numeric separator to shippedProposals in preset-env

Feature Request

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Numeric Separator is Stage 3 and shipped in Chrome 75/Firefox 70/Safari 13!

![](https://example.com/you-know-how-excited-i-am.gif)

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This means that it should be enabled via shippedProposals: true options in @babel/preset-env 🎉

It should be done similarly to this commit: https://github.com/babel/babel/pull/8438/commits/28bbd9fb0e010e077bf1e4c3ec4fa25098ea9430

1. Add it to packages/babel-preset-env/src/available-plugins.js
2. Add the compat-table mapping to packages/babel-preset-env/data/plugin-features.js (you can find the correct feature name at https://kangax.github.io/compat-table/esnext/)
3. Add it to packages/babel-preset-env/data/shipped-proposals.js
4. Run cd packages/preset-env and yarn build-data to update the data about the supported browser versions
5. Add it to @babel/preset-env-standalone (packages/babel-preset-env-standalone/src/available-plugins.js)
6. Update the test as needed (you don’t need to write new tests)
7. PR! 🎉

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If it is the first time that you contribute to Babel, follow these steps: (you need to have make and yarn available on your machine)

1. Write a comment there to let other possible contributors know that you are working on this bug.
2. Fork the repo
3. Run git clone https://github.com/<YOUR_USERNAME>/babel.git && cd babel
4. Run yarn && make bootstrap
5. Wait ⏳
6. Run make watch (or make build whenever you change a file)
7. Add a test if needed (only input.js; output.js will be automatically generated)
8. Update the code!
9. yarn jest babel-preset-env to run the tests
   • Since you don’t need to write new tests, you can run OVERWRITE=true yarn jest babel-preset-env and they will be automatically updated.
10. If it is working, run make test to run all the tests
11. Run git push and open a PR!

[Wetinee]

I’d like to try this out, with such detailed instructions above. 😉

[JLHwung]

@Wetinee has talked to me offline a bit. She’s working on it after the holiday seasons.