const { BABEL_ENV, NODE_ENV } = process.env;

const modules = BABEL_ENV === 'cjs' || NODE_ENV === 'test' ? 'commonjs' : false;

module.exports = () => ({

presets: [

[

'@babel/preset-env',

{

targets: NODE_ENV === 'test' ? { node: 'current' } : undefined,

loose: true,

modules,

},

],

'@babel/preset-react',

'@babel/preset-typescript',

],

plugins: [

'@babel/plugin-transform-flow-strip-types',

['@babel/plugin-proposal-object-rest-spread', { loose: true }],

['@babel/plugin-proposal-class-properties', { loose: true }],

modules === 'commonjs' && 'add-module-exports',

].filter(Boolean),

});