Parcel: Tree-Shaking with react-intl library makes bundle even bigger

[PutziSan]

🐛 bug report

this project which only includes React and react-intl results in following builds:
normal build (no --experimental-scope-hoisting)

$ yarn build
yarn run v1.9.4
warning package.json: No license field
$ parcel build index.html
√  Built in 32.81s.

dist\src.0a4b8332.map    ‼  2.29 MB     337ms
dist\src.0a4b8332.js     ‼  1.14 MB    13.68s
dist\index.html               159 B    18.58s
Done in 42.11s.

build with --experimental-scope-hoisting

$ yarn build --experimental-scope-hoisting
yarn run v1.9.4
warning package.json: No license field
$ parcel build index.html --experimental-scope-hoisting
√  Built in 32.43s.

dist\src.3fbcb662.js    ‼  1.32 MB    20.95s
dist\index.html              159 B    16.61s
Done in 37.49s.

With CRA the file size after gzip is 47kb (157kb non-gzipped)

🤔 Expected Behavior

The bundle should get smaller.

😯 Current Behavior

Getting bigger.

💻 Code Sample

sandbox

🌍 Your Environment

| Software | Version(s) |
| ---------------- | ---------- |
| Parcel | 1.9.7
| Node | 8.11.3
| npm/Yarn | 5.6.0 / 1.9.4
| Operating System | Win10

[mischnic]

Do you this still have this issue?

[PutziSan]

yup: I updated the dependencies (https://codesandbox.io/s/4zr09pqzo0), downloaded the sandbox-project and built it locally:
without --experimental-scope-hoisting

with --experimental-scope-hoisting

[mischnic]

Why are your JS bundles (both) so large? On macOS:

$ parcel build index.html
✨  Built in 14.37s.

dist/src.e4004e4c.map    404.38 KB     166ms
dist/src.32972fef.js     160.19 KB    13.29s
dist/index.html              159 B     875ms


$ parcel build index.html --experimental-scope-hoisting
✨  Built in 18.14s.

dist/src.482df5c1.js    155.01 KB    17.07s
dist/index.html             159 B     3.96s

[PutziSan]

Oha, then it's the operating system? I use Windows 10.

Otherwise, as I said, I have done nothing else than:

1. download project from sandbox
2. unzip
3. yarn install
4. yarn build

If it works correctly for other Windows users (can anyone confirm that?), I unfortunately have no idea why.

[mischnic]

Oha, then it's the operating system? I use Windows 10.

Can confirm, that this happens on Windows 10 and not on macOS.
Interestingly, the tree shaking test suite is currently disabled on Windows...

[mischnic]

I'm not completely sure why, but https://github.com/parcel-bundler/parcel/pull/2445 fixed your issue (December 24th, 2018). So it will be fixed in the next release

Interestingly, the tree shaking test suite is currently disabled on Windows...

This has nothing to do with this.