fix: restore default export (#33)

Author: bahmutov

__snapshots__/e2e_spec.js

@@ -28,6 +28,8 @@ var _default = {
   }
 };
 exports["default"] = _default;
+module.exports = exports.default;
+module.exports.default = exports.default;
 
 },{}],2:[function(require,module,exports){
 "use strict";

index.js

@@ -29,10 +29,14 @@ const defaultOptions = {
           babelrc: false,
           plugins: [
             ...[
-              'babel-plugin-add-module-exports', // irons out differences between ES6 modules and node exports
               '@babel/plugin-proposal-class-properties',
               '@babel/plugin-proposal-object-rest-spread',
             ].map(require.resolve),
+            // irons out differences between ES6 modules and node exports
+            // https://github.com/59naga/babel-plugin-add-module-exports
+            [require.resolve('babel-plugin-add-module-exports'), {
+              'addDefaultProperty': true,
+            }],
             [require.resolve('@babel/plugin-transform-runtime'), {
               absoluteRuntime: path.dirname(require.resolve('@babel/runtime/package')),
             }],