.babelrc format file will cause ts error, but babel.config.js won't

[iamyoki]

.babelrc format file will cause ts error, but babel.config.js won't

Error Cause

.babelrc

{
  "presets": [
    ["@babel/preset-env", {"loose": true}],
    "@babel/preset-typescript"
  ]
}

error

🎁 error /Users/yoki/Desktop/try-preconstruct-monorepo/packages/b/src/helpers.ts: Support for the experimental syntax 'flow' isn't currently enabled (1:8):
🎁 error
🎁 error > 1 | export interface Options {
🎁 error     |        ^
🎁 error   2 |   name: string
🎁 error   3 | }
🎁 error   4 |
🎁 error
🎁 error Add @babel/preset-flow (https://git.io/JfeDn) to the 'presets' section of your Babel config to enable transformation.
🎁 error If you want to leave it as-is, add @babel/plugin-syntax-flow (https://git.io/vb4yb) to the 'plugins' section to enable parsing.
🎁 info If you want to learn more about the above error, check https://preconstruct.tools/errors
🎁 info If the error is not there and you want to learn more about it, open an issue at https://github.com/preconstruct/preconstruct/issues/new

If change .babelrc file into babel.config.js

/** @type {babel.ConfigFunction} */
module.exports = (api) => {
  api.cache(true);

  return {
    presets: [
      ['@babel/preset-env', {'loose': true}],
      '@babel/preset-typescript',
    ],
  };
};

Success

🎁 info building bundles!
🎁 success built bundles!

[emmatown]

It's expected that this doesn't work based on how Babel resolves configs. If you want to write a JSON config, you can use babel.config.json.

[iamyoki]

@mitchellhamilton Thank you for your answer~
Deep down, It's expected and logical, but as a user-end, it's hard to find out what's wrong, it cost me several hours...
So I think it's better to support .babelrc format or shows explicit error or give a warning on doc site, would you like me to fix that?

[emmatown]

A PR to add something to the docs site would be great