================= require - auto ==================== typeof objectWithoutProperties: function typeof objectWithoutProperties.default: function obj: { b: 2, [Symbol(Symbol.toStringTag)]: 5 } ================= require - esm ===================== Error: Must use import to load ES Module: /packages/babel-runtime/helpers/esm/toPrimitive.js require() of ES modules is not supported. require() of /packages/babel-runtime/helpers/esm/toPrimitive.js from /test/runtime-integration/src/absolute/require-esm.cjs is an ES module file as it is a .js file whose nearest parent package.json contains "type": "module" which defines all .js files in that package scope as ES modules. Instead rename toPrimitive.js to end in .cjs, change the requiring code to use import(), or remove "type": "module" from /packages/babel-runtime/helpers/esm/package.json. =============== require - corejs ==================== typeof Set: function arr: 1,2,3