fbredius/storybook

import { TransformOptions } from '@babel/core';

const r = (s: string, local: boolean) => {
  return local ? s : require.resolve(s);
};

export const getStorybookBabelConfig = ({ local = false }: { local?: boolean } = {}) => {
  return {
    sourceType: 'unambiguous',
    presets: [
      [r('@babel/preset-env', local), { shippedProposals: true, loose: true }],
      r('@babel/preset-typescript', local),
    ],
    plugins: [
      r('@babel/plugin-transform-shorthand-properties', local),
      r('@babel/plugin-transform-block-scoping', local),
      /*
       * Added for TypeScript experimental decorator support
       * https://babeljs.io/docs/en/babel-plugin-transform-typescript#typescript-compiler-options
       */
      [r('@babel/plugin-proposal-decorators', local), { legacy: true }],
      [r('@babel/plugin-proposal-class-properties', local), { loose: true }],
      [r('@babel/plugin-proposal-private-property-in-object', local), { loose: true }],
      [r('@babel/plugin-proposal-private-methods', local), { loose: true }],
      r('@babel/plugin-proposal-export-default-from', local),
      r('@babel/plugin-syntax-dynamic-import', local),
      [r('@babel/plugin-proposal-object-rest-spread', local), { loose: true, useBuiltIns: true }],
      r('@babel/plugin-transform-classes', local),
      r('@babel/plugin-transform-arrow-functions', local),
      r('@babel/plugin-transform-parameters', local),
      r('@babel/plugin-transform-destructuring', local),
      r('@babel/plugin-transform-spread', local),
      r('@babel/plugin-transform-for-of', local),
      r('babel-plugin-macros', local),
      /*
       * Optional chaining and nullish coalescing are supported in
       * @babel/preset-env, but not yet supported in Webpack due to support
       * missing from acorn. These can be removed once Webpack has support.
       * See https://github.com/facebook/create-react-app/issues/8445#issuecomment-588512250
       */
      r('@babel/plugin-proposal-optional-chaining', local),
      r('@babel/plugin-proposal-nullish-coalescing-operator', local),
      [
        r('babel-plugin-polyfill-corejs3', local),
        {
          method: 'usage-global',
          absoluteImports: r('core-js', local),
          // eslint-disable-next-line global-require
          version: require('core-js/package.json').version,
        },
      ],
    ],
  } as TransformOptions;
};

export const getStorybookBabelDependencies = () => [
  '@babel/preset-env',
  '@babel/preset-typescript',
  '@babel/plugin-transform-shorthand-properties',
  '@babel/plugin-proposal-private-property-in-object',
  '@babel/plugin-transform-block-scoping',
  '@babel/plugin-proposal-decorators',
  '@babel/plugin-proposal-class-properties',
  '@babel/plugin-proposal-private-methods',
  '@babel/plugin-proposal-export-default-from',
  '@babel/plugin-syntax-dynamic-import',
  '@babel/plugin-proposal-object-rest-spread',
  '@babel/plugin-transform-classes',
  '@babel/plugin-transform-arrow-functions',
  '@babel/plugin-transform-parameters',
  '@babel/plugin-transform-destructuring',
  '@babel/plugin-transform-spread',
  '@babel/plugin-transform-for-of',
  'babel-plugin-macros',
  '@babel/plugin-proposal-optional-chaining',
  '@babel/plugin-proposal-nullish-coalescing-operator',
  'babel-plugin-polyfill-corejs3',
  'babel-loader',
  'core-js',
];