wrong babel cache using filepath as entry point

[Kikobeats]

Hey folks, thanks for creating this library, I found it very useful.

I'm opening this issue because I found an edge case related to how babel-loader cache works.

babel-loader uses a prop called cachedIdentifier. This property determinate if it is necessary or not re-run babel-loader process.

https://github.com/babel/babel-loader/blob/b29516266912fbc50120155fee00efb1b0a19f59/src/index.js#L61

The point here is that it reads the content of the .babelrc. All is okay.

The edge case is related with this:

{
  "plugins": [
    ["transform-define", "./path/to/config/file.js"]
  ]
}

If you use babel-plugin-transform-define specifying a file path, and then you modify the content of the file, in the next babel-loader it will be determinate that a new run is not necessary, so it will be served the last result from the cache that it's different from your expected result!

Literally, I was thinking I was crazy until discovering this.

The fix could be easiest as determinate the new way to calculate cachedIdentifier. The problem is, because in my case I'm under Next.js, that's is not something easy to do because Next.js internal doesn't contemplate this modification.

Ideally, we should do that transparently adding a bit of code inside babel-plugin-transform-define to detect the edge case, but not sure if we can do that, need to investigate around babel-loader API inside a plugin.

My current workaround is remove the cache before init the process:

rm -rf node_modules/.cache/babel-loader && npm run dev

but obviously, this is a very bad solution and slow.

any idea? 🙂

[sorosora]

I am facing the same issue.

[stevezau]

I am facing the same issue also. Was going mad trying to work out what was going on!

[ryan-roemer]

Can someone check if this is still an issue with babel-plugin-transform-define@2.0.0 and babel7? (We've removed the option to do a config file...)