fix(sql): use _.size rather than key length to also support arrays

lib/dialects/abstract/query-generator.js

@@ -1661,7 +1661,7 @@ module.exports = (function() {
         if (Array.isArray(value)) {
           value = value.map(function (item) {
             var itemQuery = self.whereItemsQuery(item, options, ' AND ');
-            if (Object.keys(item).length > 1) itemQuery = '('+itemQuery+')';
+            if (_.size(item) > 1) itemQuery = '('+itemQuery+')';
             return itemQuery;
           }).filter(function (item) {
             return item && item.length;

test/unit/sql/where.test.js

@@ -186,6 +186,12 @@ suite(Support.getTestDialectTeaser('SQL'), function() {
             default: "([group_id] = 1 OR [user_id] = 2)"
           });
         });
+
+        test("sequelize.or({group_id: 1}, {user_id: 2, role: 'admin'})", function () {
+          expectsql(sql.whereItemQuery(undefined, this.sequelize.or({group_id: 1}, {user_id: 2, role: 'admin'})), {
+            default: "([group_id] = 1 OR ([user_id] = 2 AND [role] = 'admin'))"
+          });
+        });
       });
 
       suite('$and', function () {