@nx/webpack/src/utils/web-babel-loader.js

The Nx Plugin for Webpack contains executors and generators that support building applications using Webpack.

module.exports = require('babel-loader').custom(() => {
    return {
        customOptions({ isTest, isModern, emitDecoratorMetadata, ...loader }) {
            return {
                custom: { isTest, isModern, emitDecoratorMetadata },
                loader,
            };
        },
        config(cfg, { customOptions: { isTest, isModern, emitDecoratorMetadata } }) {
            // Add hint to our babel preset so it can handle modern vs legacy bundles.
            cfg.options.caller.isModern = isModern;
            cfg.options.caller.isTest = isTest;
            cfg.options.caller.emitDecoratorMetadata = emitDecoratorMetadata;
            return cfg.options;
        },
    };
});