babel.config.js

const path = require('path');
const appVersion = require('./packages/netlify-cms-app/package.json').version;
const coreVersion = require('./packages/netlify-cms-core/package.json').version;
const isProduction = process.env.NODE_ENV === 'production';
const isTest = process.env.NODE_ENV === 'test';
const isESM = process.env.NODE_ENV === 'esm';

console.log('Build Package:', path.basename(process.cwd()));

const defaultPlugins = [
  'lodash',
  [
    'babel-plugin-transform-builtin-extend',
    {
      globals: ['Error'],
    },
  ],
  'transform-export-extensions',
  '@babel/plugin-proposal-class-properties',
  '@babel/plugin-proposal-object-rest-spread',
  '@babel/plugin-proposal-export-default-from',
  [
    'module-resolver',
    isESM
      ? {
          root: ['./src'],
          alias: {
            coreSrc: './src',
            Actions: './src/actions',
            App: './src/components/App',
            Collection: './src/components/Collection',
            Constants: './src/constants',
            Editor: './src/components/Editor',
            EditorWidgets: './src/components/EditorWidgets',
            Formats: './src/formats',
            Integrations: './src/integrations',
            Lib: './src/lib',
            MediaLibrary: './src/components/MediaLibrary',
            Reducers: './src/reducers',
            Selectors: './src/selectors',
            ReduxStore: './src/redux',
            Routing: './src/routing',
            UI: './src/components/UI',
            Workflow: './src/components/Workflow',
            ValueObjects: './src/valueObjects',
            localforage: 'localforage',
            redux: 'redux',
          },
        }
      : {
          root: path.join(__dirname, 'packages/netlify-cms-core/src/components'),
          alias: {
            coreSrc: path.join(__dirname, 'packages/netlify-cms-core/src'),
            Actions: path.join(__dirname, 'packages/netlify-cms-core/src/actions/'),
            Constants: path.join(__dirname, 'packages/netlify-cms-core/src/constants/'),
            Formats: path.join(__dirname, 'packages/netlify-cms-core/src/formats/'),
            Integrations: path.join(__dirname, 'packages/netlify-cms-core/src/integrations/'),
            Lib: path.join(__dirname, 'packages/netlify-cms-core/src/lib/'),
            Reducers: path.join(__dirname, 'packages/netlify-cms-core/src/reducers/'),
            Selectors: path.join(__dirname, 'packages/netlify-cms-core/src/selectors/'),
            ReduxStore: path.join(__dirname, 'packages/netlify-cms-core/src/redux/'),
            Routing: path.join(__dirname, 'packages/netlify-cms-core/src/routing/'),
            ValueObjects: path.join(__dirname, 'packages/netlify-cms-core/src/valueObjects/'),
            localforage: 'localforage',
            redux: 'redux',
          },
        },
  ],
];

const presets = () => {
  return ['@babel/preset-react', '@babel/preset-env'];
};

const plugins = () => {
  if (isESM) {
    return [
      ...defaultPlugins,
      [
        'emotion',
        {
          sourceMap: true,
          autoLabel: true,
        },
      ],
      [
        'transform-define',
        {
          NETLIFY_CMS_APP_VERSION: `${appVersion}`,
          NETLIFY_CMS_CORE_VERSION: `${coreVersion}`,
        },
      ],
      [
        'inline-react-svg',
        {
          svgo: {
            plugins: [{ removeViewBox: false }],
          },
        },
      ],
    ];
  }

  if (isTest) {
    return [
      ...defaultPlugins,
      [
        'emotion',
        {
          sourceMap: false,
          autoLabel: false,
        },
      ],
      [
        'inline-react-svg',
        {
          svgo: {
            plugins: [{ removeViewBox: false }],
          },
        },
      ],
    ];
  }

  if (!isProduction) {
    return [
      ...defaultPlugins,
      [
        'emotion',
        {
          sourceMap: true,
          autoLabel: true,
        },
      ],
      'react-hot-loader/babel',
    ];
  }

  return [
    ...defaultPlugins,
    [
      'emotion',
      {
        sourceMap: true,
        autoLabel: true,
      },
    ],
  ];
};

module.exports = {
  presets: presets(),
  plugins: plugins(),
};