Map plugins to transformers and vice versa

[andrewmiller1]

Feature Request

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You guys have done a fantastic job on babel.

An extension of #6205

I have an issue when I'm dealing with a syntax plugin but don't know its associated transformer plugin and vice versa.

My view:

Using plugins listed in stage preset deprecation error message.

Expecting all experimental features to be enabled and configured. But run into:

SyntaxError ... Support for the experimental syntax 'classPrivateMethods' isn't currently enabled ...
...
missingPlugin: [ 'classPrivateMethods' ],
...

Look into documentation, and see

NOTE: transform plugins automatically enable the syntax plugins. So you don't need to specify the syntax plugin if the corresponding transform plugin is used already.

I couldn't initially confirm which transformer if any associated with this syntax plugin. Names were changing in the ecma proposals and proposals were being combined as well.

During that point in time I didn't know which situation I was in:

• The stage preset error didn't list all the plugins
• Only parsing was supported for private methods and I wouldn't be able to get a transformer
• There was a bug in the code

After an hour of researching the ecma repositories and babel github issues and development, I found what I needed: #8130 (comment)

Describe the solution you'd like
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Mainly, mimic how proposals are referenced but for the respective feature.

Describe alternatives you've considered
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Reference babel's relevant development tracker issue for the relevant feature in progress, in documentation / error messages

Teachability, Documentation, Adoption, Migration Strategy
If you can, explain how users will be able to use this and possibly write out a version the docs.
Maybe a screenshot or design?

From https://babeljs.io/docs/en/next/babel-parser:

Before

classPrivateMethods (proposal)	class A { #c() {} }

After

classPrivateMethods (plugin, proposal)	class A { #c() {} }

And similar solution on the transformer documentation (maybe include into error messages referenced in the issue linked at the top of this post too).

There are further improvements we can do that relate to this issue. But for an easy and effective solution now, we can start with linking the transformers and the plugins where we might need to find them.

[babel-bot]

Hey @andrewmiller1! We really appreciate you taking the time to report an issue. The collaborators
on this project attempt to help as many people as possible, but we're a limited number of volunteers,
so it's possible this won't be addressed swiftly.

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[nicolo-ribaudo]

Babel now throws

Support for the experimental syntax 'classProperties' isn't currently enabled (2:5):

  1 | class A {
> 2 |   x = 2
    |     ^
  3 | }

Add @babel/plugin-proposal-class-properties (https://git.io/vb4SL) to the 'plugins' section of your Babel config to enable transformation.
If you want to leave it as-is, add @babel/plugin-syntax-class-properties (https://git.io/vb4yQ) to the 'plugins' section to enable parsing.