.babelrc
{
"presets": [
["@babel/preset-env", {
"useBuiltIns": "usage", // uses browserslist config in package.json to auto-inject polyfills
"modules": false, // don't transform es6 modules; webpack 4 handles them natively
"corejs": 3 // specify the corejs version to use for polyfilling
}]
],
"env": {
"test": {
"presets": ["@babel/preset-env"],
}
}
}