Deriving babel.json

janat08 · February 23, 2019, 5:15pm

Is there a way to determine what babel settings are being used by meteor, or get their approximation so that you could use tools that require it like testers or lettings the code be build without installing meteor.

coagmano · February 25, 2019, 12:11am

Yes, the babel settings are generated by the code here: https://github.com/meteor/babel/blob/master/options.js

Unless you’re running an old Meteor, it’s very likely short circuiting to getDefaultsForNode8

github.com

meteor/babel/blob/master/options.js#L164


  if (features.runtime === false) {
    return null;
  }
}


// Import helpers from the babel-runtime package rather than redefining
// them at the top of each module.
return require("@babel/plugin-transform-runtime");
}


function getDefaultsForNode8(features) {
const plugins = [];


// Compile import/export syntax with Reify.
plugins.push([reifyPlugin, {
  generateLetDeclarations: true,
  enforceStrictMode: false
}]);


// Support Flow type syntax by simply stripping it out.
plugins.push(

Unfortunately it’s not a simple json file since it needs to handle differential compilation for old node, new node, old browsers and new browsers, maybe React, maybe Typescript, and adding Fibers support to async/await