Cache is not invalidated after babelrc is created

[Codesleuth]

🐛 bug report

Build cache is not updated when .babelrc file is created. Specifically for my use-case, transform-react-jsx.pragma setting is not respected.

🎛 Configuration (.babelrc, package.json, cli command)

File to add after the initial build

{
  "plugins": [
    ["transform-react-jsx", { "pragma": "m" }]
  ]
}

🤔 Expected Behavior

When restarting parcel, specified pragma for JSX files should be used.

😯 Current Behavior

The first build will produce a cache which uses the default React pragma setting; after creating the .babelrc file, the next build will emit the same error.

Uncaught ReferenceError: React is not defined

💁 Possible Solution

Invalidate the cache after .babelrc is added to the project.

🔦 Context

I was beginning a new project where I installed parcel and set up an initial JSX component with mithril. As always, I forget to create a .babelrc file, and realise this when the first build displays this error. After adding the file and re-launching parcel, I expected the build to be fixed.

See the demo project for full context.

💻 Code Sample

Steps and demo assets available here: https://github.com/Codesleuth/parcel-babelrc-rebuild-bug

🌍 Your Environment

Software	Version(s)
Parcel	1.8.1
Node	8.11.1
npm/Yarn	5.8.0
Operating System	Ubuntu 16.04 LTS

[DeMoorJasper]

The cache invalidating currently only triggers on file update not file creation. (file refers to .babelrc config)

I'm a bit confused after reading your issue, did it happen on creation or update?
As the issue states both

[Codesleuth]

That explains it then, it was on creation. You can see in the steps of the demo project that the file doesn't exist on first build, is created and rebuilt, and there's no cache change.

I've updated the title and report, sorry for the confusion there.

[nicolaisueper]

I assume the cache should be invalidated too when the "babel": {} property was added to the project's package.json?

[DeMoorJasper]

package.json changes should invalidate every file, as every asset has a getPackage property

[nicolaisueper]

@DeMoorJasper I'd love to tackle this. Can you give me a hint where to start?

I thought about subscribing to every file which gets created inside the project root and check if the filename equals to .babelrc

[devongovett]

Waiting on this babel PR to be released and then we should be able to implement this: babel/babel#11906.