export default {
  "presets": [
    [
      "@babel/preset-env",
      {
        // `transform-typeof-symbol` plugin adds a `_typeof` function.
        // Because that function is not added as a "dependency" of a worker function,
        // it results in a runtime error when running in CommonJS environment:
        // "ReferenceError: _typeof is not defined".
        // A workaround is to disable this plugin.
        // If the code doesn't include `typeof ...Symbol...` statements
        // then disabling this plugin is supposed to not introduce any bugs.
        // https://babeljs.io/docs/babel-plugin-transform-typeof-symbol
        "exclude": ["@babel/plugin-transform-typeof-symbol"]
      }
    ]
  ],

  // `transform-spread` plugin adds a `_toConsumableArray` function.
  // Because that function is not added as a "dependency" of a worker function,
  // it results in a runtime error when running in CommonJS environment:
  // "ReferenceError: _toConsumableArray is not defined".
  // A workaround is to tell it to assume that any "iterable" is an array,
  // i.e. anything that is used in a `for of` loop is an array, etc.
  // If the code doesn't pass anything other than arrays to `for of` loops, etc,
  // then disabling this plugin is supposed to not introduce any bugs.
  // https://babeljs.io/docs/babel-plugin-transform-spread
  "assumptions": {
    "iterableIsArray": true
  }
}