transaction support for belongsTo

lib/associations/belongs-to.js

@@ -70,14 +70,15 @@ module.exports = (function() {
     var self     = this
       , accessor = Utils._.camelize('set_' + (this.options.as || Utils.singularize(this.target.tableName, this.target.options.language)))
 
-    obj[accessor] = function(associatedObject) {
+    obj[accessor] = function(associatedObject, options) {
       var primaryKeys = !!associatedObject && !!associatedObject.daoFactory ? Object.keys(associatedObject.daoFactory.primaryKeys) : []
         , primaryKey = primaryKeys.length === 1 ? primaryKeys[0] : 'id'
 
       this[self.identifier] = associatedObject ? associatedObject[primaryKey] : null
+      options               = Utils._.extend({ fields: [ self.identifier ], allowNull: [self.identifier] }, options)
 
       // passes the changed field to save, so only that field get updated.
-      return this.save([ self.identifier ], {allowNull: [self.identifier]})
+      return this.save(options)
     }
 
     return this

test/associations/belongs-to.test.js

@@ -21,6 +21,32 @@ describe(Support.getTestDialectTeaser("BelongsTo"), function() {
   })
 
   describe('setAssociation', function() {
+    it('supports transactions', function(done) {
+      Support.prepareTransactionTest(this.sequelize, function(sequelize) {
+        var User  = sequelize.define('User', { username: Support.Sequelize.STRING })
+          , Group = sequelize.define('Group', { name: Support.Sequelize.STRING })
+
+        Group.belongsTo(User)
+
+        sequelize.sync({ force: true }).success(function() {
+          User.create({ username: 'foo' }).success(function(user) {
+            Group.create({ name: 'bar' }).success(function(group) {
+              sequelize.transaction(function(t) {
+                group.setUser(user, { transaction: t }).success(function() {
+                  Group.all().success(function(groups) {
+                    groups[0].getUser().success(function(associatedUser) {
+                      expect(associatedUser).to.be.null
+                      t.rollback().success(function() { done() })
+                    })
+                  })
+                })
+              })
+            })
+          })
+        })
+      })
+    })
+
     it('can set the association with declared primary keys...', function(done) {
       var User = this.sequelize.define('UserXYZ', { user_id: {type: DataTypes.INTEGER, primaryKey: true }, username: DataTypes.STRING })
         , Task = this.sequelize.define('TaskXYZ', { task_id: {type: DataTypes.INTEGER, primaryKey: true }, title: DataTypes.STRING })