[hotfix] Use same targets for fields as for private methods

[nicolo-ribaudo]

Q	A
Fixed Issues?	https://twitter.com/IAmTrySound/status/1265639257571540993
Patch: Bug Fix?
Major: Breaking Change?
Minor: New Feature?
Tests Added + Pass?	Yes
Documentation PR Link
Any Dependency Changes?
License	MIT

babel.transformSync("class A { x }", {
  configFile: false,
  presets: [
    ["@babel/env", {
      targets: { node: 12 },
      shippedProposals: true,
    }],
  ],
});

The above code doesn't work with Babel 7.10.0 because

1. Class fields are supported, so the plugin is not enabled
2. Private methods are not supported, so the plugin is enabled and we use create-class-features
3. When transforming a class with the create-class-features, we check if all the eeded features are enabled. We don't support transforming private methods without transforming private fields, so we throw an error

I'm working on removing the dependency between the two plugins, but this quick and dirty hack makes preset-env work until I open a better PR. I would like to merge this one for the next patch release (today?).

cc @TrySound

[babel-bot]

Build successful! You can test your changes in the REPL here: https://babeljs.io/repl/build/23004/

[codesandbox-ci]

This pull request is automatically built and testable in CodeSandbox.

To see build info of the built libraries, click here or the icon next to each commit SHA.

Latest deployment of this branch, based on commit 0c6350d:

Sandbox	Source
ecstatic-elbakyan-xiyow	Configuration
musing-field-r3ilg	Configuration

[TrySound]

Yay, thanks!

[TrySound]

@nicolo-ribaudo I just got the same problem with numeric separators in node 13

[nicolo-ribaudo]

That is unexpected 🤔

The problem fixed by this PR is that the private methods and class fields plugins depend on each other, and on Node.js 12 only one of them was enabled.

Numeric separators don't have such hidden dependency 🤔

[TrySound]

This is weird, I got syntax error similar to class properties. And only in node 13 but not 12

[nicolo-ribaudo]

What is the exact error?

[TrySound]

[!] Error: Identifier directly after number points to object with numeric separator.

This is very weird, syntax plugin is included. Here's debug output

@babel/preset-env: `DEBUG` option

Using targets:
{
  "node": "13.12"
}

Using modules transform: false

Using plugins:
  syntax-numeric-separator { "node":"13.12" }
  proposal-class-properties { "node":"13.12" }
  proposal-private-methods { "node":"13.12" }
  proposal-nullish-coalescing-operator { "node":"13.12" }
  proposal-optional-chaining { "node":"13.12" }
  syntax-json-strings { "node":"13.12" }
  syntax-optional-catch-binding { "node":"13.12" }
  syntax-async-generators { "node":"13.12" }
  syntax-object-rest-spread { "node":"13.12" }
  syntax-dynamic-import { "node":"13.12" }
  syntax-top-level-await { "node":"13.12" }

Using polyfills: No polyfills were added, since the `useBuiltIns` option was not set.

By the way same problem with 14.3. Though I cannot reproduce it in isolated example.

[nicolo-ribaudo]

Could you share your lockfile in a gist?

Also, if you can put Error.stackTraceLimit = Infinity somewhere (for example, in your Babel config, but it could be anywhere) the full stack trace would help.

[TrySound]

Oh, I get it. Sorry, it's rollup syntax error 🤦