feat(promises): more refactoring

changelog.md

 Notice: All 1.7.x changes are present in 2.0.x aswell
 
+# next
+#### Breaking changes
+- Sequelize now returns promises instead of its custom event emitter from most calls. This affects methods that return multiple values (like `findOrCreate` or `findOrInitialize`). If your current callbacks do not accept the 2nd success parameter you might be seeing an array as the first param. Either use `.spread()` for these methods or add another argument to your callback: `.success(instance)` -> `.success(instance, created)`.
+- `.success()`/`.done()` and any other non promise methods are now deprecated (we will keep the codebase around for a few versions though). on('sql') persists for debugging purposes.
+
 # v2.0.0-dev11
 ### Caution: This release contains many changes and is highly experimental
 - [PERFORMANCE] increased build performance when using include, which speeds up findAll etc.

lib/associations/belongs-to.js

@@ -113,15 +113,9 @@ module.exports = (function() {
         options.transaction = fieldsOrOptions.transaction
       }
 
-      return new Utils.CustomEventEmitter(function(emitter) {
-        association.target
-          .create(values, fieldsOrOptions)
-          .proxy(emitter, { events: ['error', 'sql'] })
-          .success(function(newAssociatedObject) {
-            instance[association.accessors.set](newAssociatedObject, options)
-              .proxy(emitter)
-          })
-      }).run()
+      return association.target.create(values, fieldsOrOptions).then(function(newAssociatedObject) {
+        return instance[association.accessors.set](newAssociatedObject, options)
+      })
     }
 
     return this

lib/dao.js

@@ -400,7 +400,7 @@ module.exports = (function() {
    * @param {Object} [options.fields] An alternative way of setting which fields should be persisted
    * @param {Transaction} [options.transaction]
    *
-   * @return {EventEmitter}
+   * @return {Promise}
    */
   DAO.prototype.save = function(fieldsOrOptions, options) {
     if (fieldsOrOptions instanceof Array) {
@@ -585,7 +585,7 @@ module.exports = (function() {
    * @param {Array} [options.skip] An array of strings. All properties that are in this array will not be validated
    * @see {DAOValidator}
    * 
-   * @return {EventEmitter}
+   * @return {Promise}
    */
   DAO.prototype.validate = function(options) {
     return new DaoValidator(this, options).validate()

lib/promise.js

@@ -139,7 +139,7 @@ SequelizePromise.prototype.emit = function(evt) {
 
   if (evt === 'success') {
     this.seqResolve.apply(this, args);
-  } else if (evt === 'error') {;
+  } else if (evt === 'error') {
     this.seqReject.apply(this, args);
   } else {
     // Needed to transfer sql across .then() calls
@@ -170,7 +170,11 @@ SequelizePromise.prototype.emit = function(evt) {
 
 SequelizePromise.prototype.success =
 SequelizePromise.prototype.ok = function(fct) {
-  return this.then(fct);
+  if (fct.length > 1) {
+    return this.spread(fct);
+  } else {
+    return this.then(fct);
+  }
 }
 
 /**

test/dao-factory.test.js

@@ -569,9 +569,9 @@ describe(Support.getTestDialectTeaser("DAOFactory"), function () {
         User.sync({ force: true }).success(function() {
           sequelize.transaction(function(t) {
             User.create({ username: 'foo' }, { transaction: t }).success(function() {
-              User.findOrInitialize({ username: 'foo' }).success(function(user1) {
-                User.findOrInitialize({ username: 'foo' }, { transaction: t }).success(function(user2) {
-                  User.findOrInitialize({ username: 'foo' }, { foo: 'asd' }, { transaction: t }).success(function(user3) {
+              User.findOrInitialize({ username: 'foo' }).spread(function(user1) {
+                User.findOrInitialize({ username: 'foo' }, { transaction: t }).spread(function(user2) {
+                  User.findOrInitialize({ username: 'foo' }, { foo: 'asd' }, { transaction: t }).spread(function(user3) {
                     expect(user1.isNewRecord).to.be.true
                     expect(user2.isNewRecord).to.be.false
                     expect(user3.isNewRecord).to.be.false
@@ -592,7 +592,7 @@ describe(Support.getTestDialectTeaser("DAOFactory"), function () {
         this.User.create({ username: 'Username' }).success(function (user) {
           self.User.findOrInitialize({
             username: user.username
-          }).success(function (_user, initialized) {
+          }).spread(function (_user, initialized) {
             expect(_user.id).to.equal(user.id)
             expect(_user.username).to.equal('Username')
             expect(initialized).to.be.false
@@ -608,7 +608,7 @@ describe(Support.getTestDialectTeaser("DAOFactory"), function () {
           self.User.findOrInitialize({
             username: user.username,
             data: user.data
-          }).success(function (_user, initialized) {
+          }).spread(function (_user, initialized) {
             expect(_user.id).to.equal(user.id)
             expect(_user.username).to.equal('Username')
             expect(_user.data).to.equal('data')
@@ -626,7 +626,7 @@ describe(Support.getTestDialectTeaser("DAOFactory"), function () {
             data: 'ThisIsData'
           }
 
-        this.User.findOrInitialize(data, default_values).success(function(user, initialized) {
+        this.User.findOrInitialize(data, default_values).spread(function(user, initialized) {
           expect(user.id).to.be.null
           expect(user.username).to.equal('Username')
           expect(user.data).to.equal('ThisIsData')

test/dao-factory/create.test.js

@@ -67,7 +67,7 @@ describe(Support.getTestDialectTeaser("DAOFactory"), function () {
       this.User.create(data).success(function (user) {
         self.User.findOrCreate({
           username: user.username
-        }).success(function (_user, created) {
+        }).spread(function (_user, created) {
           expect(_user.id).to.equal(user.id)
           expect(_user.username).to.equal('Username')
           expect(created).to.be.false

test/dao-factory/scopes.test.js

@@ -245,7 +245,7 @@ describe(Support.getTestDialectTeaser("DAOFactory"), function () {
     })
 
     it("should have no problem performing findOrCreate", function(done) {
-      this.ScopeMe.findOrCreate({username: 'fake'}).success(function(user) {
+      this.ScopeMe.findOrCreate({username: 'fake'}).spread(function(user) {
         expect(user.username).to.equal('fake')
         done()
       })

test/promise.test.js

@@ -319,16 +319,6 @@ describe(Support.getTestDialectTeaser("Promise"), function () {
       this.User.create({ id: 1, aNumber: 0, bNumber: 0 }).done(done)
     })
 
-    it('with then', function (done) {
-      this.User
-        .findOrCreate({ id: 1})
-        .then(function(user) {
-          expect(user.id).to.equal(1)
-          expect(arguments.length).to.equal(1)
-          done()
-        })
-    })
-
     describe('with spread', function () {
       it('user not created', function (done) {
         this.User