Add support for calling promise.done with no arguments. Closes #2161

changelog.md

 # Next
 # Next
 - [BUG] Fixed an issue with foreign key object syntax for hasOne and belongsTo
 - [BUG] Fixed an issue with foreign key object syntax for hasOne and belongsTo
 - [FEATURE] Added `field` and `name` to the object form of foreign key definitions
 - [FEATURE] Added `field` and `name` to the object form of foreign key definitions
+- [FEATURE] Added support for calling `Promise.done`, thus explicitly ending the promise chain by calling done with no arguments. Done with a function argument still continues the promise chain, to maintain BC.
 
 
 #### Backwards compatability changes
 #### Backwards compatability changes
 - The `fieldName` property, used in associations with a foreign key object `(A.hasMany(B, { foreignKey: { ... }})`, has been renamed to `name` to avoid confusion with `field`. 
 - The `fieldName` property, used in associations with a foreign key object `(A.hasMany(B, { foreignKey: { ... }})`, has been renamed to `name` to avoid confusion with `field`. 

lib/promise.js

@@ -117,8 +117,14 @@ SequelizePromise.prototype.error = function(fct) {
 * @alias complete
 * @alias complete
 * @return this
 * @return this
 */
 */
+var bluebirdDone = Promise.prototype.done;
 SequelizePromise.prototype.done =
 SequelizePromise.prototype.done =
 SequelizePromise.prototype.complete = function(fct) {
 SequelizePromise.prototype.complete = function(fct) {
+  if (!fct) {
+    // If no callback is provided, map to the promise.done function, which explicitly ends a promise chain
+    return bluebirdDone.call(this);
+  }
+
   if (fct.length > 2) {
   if (fct.length > 2) {
     return this.spread(function() {
     return this.spread(function() {
       fct.apply(null, [null].concat(Array.prototype.slice.call(arguments)));
       fct.apply(null, [null].concat(Array.prototype.slice.call(arguments)));