babel.config.js
function isBabelNode(caller) {
return !!(caller && caller.name === '@babel/node')
}
module.exports = api => {
const env = api.env()
const isNode = api.caller(isBabelNode)
const isTest = env === 'test'
const useESModules = !isTest && !isNode
return {
presets: [
[
'@babel/preset-env',
{
modules: useESModules ? false : 'commonjs',
loose: true,
},
],
'@babel/preset-react',
],
plugins: [
[
'@babel/plugin-proposal-decorators',
{
legacy: true,
},
],
['@babel/plugin-proposal-class-properties', { loose: true }],
['@babel/plugin-proposal-object-rest-spread', { loose: true }],
['@babel/transform-runtime', { useESModules }],
'@babel/plugin-transform-react-constant-elements',
],
}
}