Cleanup

node_modules/mongoose/lib/schema/mixed.js

@@ -7,6 +7,7 @@
 const SchemaType = require('../schematype');
 const symbols = require('./symbols');
 const isObject = require('../helpers/isObject');
+const utils = require('../utils');
 
 /**
  * Mixed SchemaType constructor.
@@ -103,6 +104,9 @@ Mixed.set = SchemaType.set;
  */
 
 Mixed.prototype.cast = function(val) {
+  if (val instanceof Error) {
+    return utils.errorToPOJO(val);
+  }
   return val;
 };