check if object has own property in "var in" loop

lib/dialects/mysql/query-generator.js

@@ -15,6 +15,7 @@ module.exports = (function() {
         , attrStr = []
 
       for (var attr in attributes) {
+        if (attributes.hasOwnProperty(attr)) {
           var dataType = attributes[attr]
 
           if (Utils._.includes(dataType, 'PRIMARY KEY')) {
@@ -24,6 +25,7 @@ module.exports = (function() {
             attrStr.push(Utils.addTicks(attr) + " " + dataType)
           }
         }
+      }
 
       var values = {
         table: Utils.addTicks(tableName),
@@ -380,12 +382,14 @@ module.exports = (function() {
       var fields = []
 
       for (var name in factory.attributes) {
+        if (factory.attributes.hasOwnProperty(name)) {
           var definition = factory.attributes[name]
 
           if (definition && (definition.indexOf('auto_increment') > -1)) {
             fields.push(name)
           }
         }
+      }
 
       return fields
     }