fixed an issue with external globals defined in CJS that happen to have a 'default' export

Author: beatfactor

lib/utils/requireModule.js

@@ -18,7 +18,7 @@ module.exports = function (fullpath) {
     return import(fullpath).then(result => (result.default || {}));
   }
 
-  if (exported && Object.prototype.hasOwnProperty.call(exported, 'default')) {
+  if (exported && Object.prototype.hasOwnProperty.call(exported, 'default') && Object.keys(exported).length === 1) {
     return exported.default;
   }
 

test/extra/external-globals.js

@@ -1,6 +1,8 @@
 const assert = require('assert');
 
 module.exports = {
+  'default': {},
+
   async before() {
     this.isFungus = true;
   },