V3 Fix issues #6356 (#7164)

* fix 5755 for v3 branch

* fix ER_EMPTY_QUERY error on update with virtual fields

* fix review

* [ci skip] changelog for issue

changelog.md

 # 3.30.1
 # 3.30.1
 - [FIXED] `sourceKey` FOR `hasMany` now also works if a `where` was specified in an `include` [#7141](https://github.com/sequelize/sequelize/issues/7141)
 - [FIXED] `sourceKey` FOR `hasMany` now also works if a `where` was specified in an `include` [#7141](https://github.com/sequelize/sequelize/issues/7141)
 - [CHANGED] Updated deprecated `node-uuid` package to `uuid` [#7148](https://github.com/sequelize/sequelize/pull/7148)
 - [CHANGED] Updated deprecated `node-uuid` package to `uuid` [#7148](https://github.com/sequelize/sequelize/pull/7148)
+- [FIXED] Updating `VIRTUAL` field throw `ER_EMPTY_QUERY` [#6356](https://github.com/sequelize/sequelize/issues/6356)
 
 
 # 3.30.0
 # 3.30.0
 - [FIXED] `removeColumn` method to support dropping primaryKey column (MSSQL) [#7081](https://github.com/sequelize/sequelize/pull/7081)
 - [FIXED] `removeColumn` method to support dropping primaryKey column (MSSQL) [#7081](https://github.com/sequelize/sequelize/pull/7081)

lib/instance.js

@@ -650,7 +650,13 @@ Instance.prototype.save = function(options) {
       });
       });
     })
     })
     .then(function() {
     .then(function() {
-      if (!options.fields.length) return this;
+      var realFields = [];
+      options.fields.forEach(function(field) {
+        if (!self.Model._isVirtualAttribute(field)) {
+          realFields.push(field);
+        }
+      });
+      if (!realFields.length) return this;
       if (!this.changed() && !this.isNewRecord) return this;
       if (!this.changed() && !this.isNewRecord) return this;
 
 
       var values = Utils.mapValueFieldNames(this.dataValues, options.fields, this.Model)
       var values = Utils.mapValueFieldNames(this.dataValues, options.fields, this.Model)

test/integration/instance.test.js

@@ -1213,6 +1213,25 @@ describe(Support.getTestDialectTeaser('Instance'), function() {
           });
           });
         });
         });
       });
       });
+
+      it('should not throw ER_EMPTY_QUERY if changed only virtual fields', function() {
+        var User = this.sequelize.define('User' + config.rand(), {
+          name: DataTypes.STRING,
+          bio: {
+            type: DataTypes.VIRTUAL,
+            get: function() {
+              return 'swag';
+            }
+          }
+        }, {
+          timestamps: false
+        });
+        return User.sync({force: true}).then(function() {
+          return User.create({ name: 'John', bio: 'swag 1' }).then(function(user) {
+            return user.update({ bio: 'swag 2' }).should.be.fulfilled;
+          });
+        });
+      });
     });
     });
 
 
     it('updates with function and column value', function() {
     it('updates with function and column value', function() {