[Bug]: sourceFileName vs. sourceFilename scattered differently over project, sometimes typed wrong

[wooorm]

• Would you like to work on a fix?

How are you using Babel?

Programmatic API (babel.transform, babel.parse)

Input code

n/a

Configuration file name

No response

Configuration

n/a

Current and expected behavior

  function myFancyBabelPlugin() {
    return {
      parserOverride(contents, options) {
        if (
          options.sourceFileName &&

^-- type error “Did you mean 'sourceFilename'”, but sourceFilename is undefined and sourceFileName is set.
A bit of searching shows differently cased values: https://github.com/babel/babel/search?q=sourceFilename+path%3Apackages.

Environment

$ npx envinfo --preset
Need to install the following packages:
  envinfo
Ok to proceed? (y) y

No "true" preset found.

Possible solution

picking either

Additional context

Actual code is here: https://github.com/wooorm/xdm/blob/main/test/babel.js#L37-L41.

[babel-bot]

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[fedeci]

That's because different packages are now using different option name. We may align the syntax in Babel 8 because it is a breaking change. I would prefer to replace fileName with filename in @babel/cli instead of the opposite.

[wooorm]

I can understand differently cases due to history, and would welcome a single case. But it remains that the types are incorrect, and fixing that doesn’t have to be a major

[nicolo-ribaudo]

We can start by allowing both the current "mixed" versions and the consistent versions in the next minor; then in Babel 8 we can remove the "mixed" versions (and yes, we should fix the type definitions).

[fedeci]

I did some research while changing all occurrences of sourceFileName with sourceFilename and discovered that the error of the issue is caused by the following lines

babel/packages/babel-core/src/transformation/normalize-opts.ts

Lines 29 to 33 in 90d5eb7

	parserOpts: {
	sourceType:
	path.extname(filenameRelative) === ".mjs" ? "module" : sourceType,
	sourceFileName: filename,

We are setting the unused sourceFileName parser option and, in fact, commenting line 33 results in no tests failing, because there is "nothing to break".