babel.config.js
module.exports = function (api) {
var validEnv = ["development", "test", "production"];
var currentEnv = api.env();
var isDevelopmentEnv = api.env("development");
var isProductionEnv = api.env("production");
var isTestEnv = api.env("test");
if (!validEnv.includes(currentEnv)) {
throw new Error(
"Please specify a valid `NODE_ENV` or " +
'`BABEL_ENV` environment variables. Valid values are "development", ' +
'"test", and "production". Instead, received: ' +
JSON.stringify(currentEnv) +
".",
);
}
return {
presets: [
isTestEnv && [
require("@babel/preset-env").default,
{
targets: {
node: "current",
},
},
],
(isProductionEnv || isDevelopmentEnv) && [
require("@babel/preset-env").default,
{
forceAllTransforms: true,
useBuiltIns: "entry",
corejs: 3,
modules: false,
exclude: ["transform-typeof-symbol"],
},
],
].filter(Boolean),
plugins: [].filter(Boolean),
};
};