babel-plugin-transform-require-default

0.1.7 verified Sat Apr 25 auth: no javascript maintenance

A Babel plugin (v0.1.7, last updated 2018) that automatically transforms CommonJS require() calls to access .default for ES modules that use __esModule. Addresses Babel 6/7's breaking change where exported defaults are no longer assigned to module.exports, requiring manual .default access. Helps maintain backward compatibility in mixed ES module / CommonJS codebases. Use with caution: modifies module resolution behavior and may cause unintended side effects. Consider alternatives like using ES import syntax or newer Babel interop settings.

Common errors

error TypeError: require(...).default is not a function ↓

cause Module exports a function directly, not as default export. Plugin incorrectly adds .default.

fix

Add the module to the exclude list: exclude: ["my-module"]

error Module "lodash" has no default export ↓

cause Plugin transforms require('lodash') to require('lodash').default, but lodash doesn't have __esModule.

fix

Use exclude: ['lodash'] or set strict mode.

Warnings

breaking Plugin modifies all require() calls to add default interop, which may break modules that don't export defaults or that rely on the raw module object. ↓

fix Use exclude option to skip modules that don't need default interop (e.g., lodash, React).

breaking Plugin uses __esModule heuristic; modules that don't set __esModule but have a default export will still be transformed, causing 'default.default' access. ↓

fix Ensure all affected modules set __esModule, or use exclude to skip them.

gotcha Plugin does not handle dynamic require() with variables or computed expressions. ↓

fix Use static require() calls if you need transformation.

gotcha Plugin may interfere with other Babel plugins that also transform require (e.g., babel-plugin-import). ↓

fix Test carefully with your plugin stack, and adjust plugin ordering.

Install

npm install babel-plugin-transform-require-default

yarn add babel-plugin-transform-require-default

pnpm add babel-plugin-transform-require-default

Imports

default

wrong

require('babel-plugin-transform-require-default').default

correct

module.exports = { plugins: [['transform-require-default', { exclude: /lodash/ }]] }

The plugin exports a function, not an object. It does not have a default export; it's a CommonJS module.

Quickstart

Configures the Babel plugin to transform require() calls, excluding certain modules, and shows the result of the transformation.

// .babelrc or babel.config.js
module.exports = {
  plugins: [
    ['transform-require-default', {
      exclude: ['lodash', /^react/]
    }]
  ]
};

// Before:
const a = require('a');

// After:
function __require_default_func__(module) { return module && module.__esModule ? module["default"] : module; }
const a = __require_default_func__(require('a'));