additional should not be merged

Author: aduh95

lib/config.js

@@ -32,10 +32,12 @@ export function getMergedConfig(dir, home, additional) {
       ...Object.getOwnPropertyDescriptors(globalConfig),
       ...Object.getOwnPropertyDescriptors(projectConfig),
       ...Object.getOwnPropertyDescriptors(localConfig),
-      ...(additional && Object.getOwnPropertyDescriptors(additional)),
     });
   }
-  return mergedConfig;
+  return additional ? Object.create(null, {
+      ...Object.getOwnPropertyDescriptors(mergedConfig),
+      ...Object.getOwnPropertyDescriptors(additional),
+    }) : mergedConfig;
 };
 export function clearCachedConfig() {
   mergedConfig = null;