fix(hooks): normalize Model.hooks to arrays (if a user passed a single method it…

… failed), closes #3179

lib/hooks.js

@@ -152,12 +152,10 @@ Hooks.addHook = function(hookType, name, fn) {
     name = null;
   }
 
-  // Aliases
   hookType = hookAliases[hookType] || hookType;
 
-  // Just in case if we override the default DAOFactory.options
   this.options.hooks[hookType] = this.options.hooks[hookType] || [];
-  this.options.hooks[hookType][this.options.hooks[hookType].length] = !!name ? {name: name, fn: fn} : fn;
+  this.options.hooks[hookType].push(!!name ? {name: name, fn: fn} : fn);
   return this;
 };
 

lib/model.js

@@ -46,7 +46,11 @@ module.exports = (function() {
     this.associations = {};
     this.modelManager = this.daoFactoryManager = null;
     this.name = name;
-    this.options.hooks = this.replaceHookAliases(this.options.hooks);
+    this.options.hooks = _.mapValues(this.replaceHookAliases(this.options.hooks), function (hooks) {
+      if (!Array.isArray(hooks)) hooks = [hooks];
+      return hooks;
+    });
+
     this.scopeObj = {};
     this.sequelize = options.sequelize;
     this.underscored = this.underscored || this.underscoredAll;

test/integration/hooks.test.js

@@ -5877,4 +5877,27 @@ describe(Support.getTestDialectTeaser('Hooks'), function() {
       });
     });
   });
+
+  describe('#addHook', function() {
+    it('should add additinoal hook when previous exists', function() {
+      var hook1 = sinon.spy()
+        , hook2 = sinon.spy()
+        , Model;
+
+      Model = this.sequelize.define('Model', { 
+        name: Sequelize.STRING 
+      }, {
+        hooks: { beforeCreate: hook1 }
+      });
+
+      Model.addHook('beforeCreate', hook2);
+
+      return Model.sync({ force: true }).then(function() {
+        return Model.create({ name: 'bob' });
+      }).then(function() {
+        expect(hook1.calledOnce).to.be.ok;
+        expect(hook2.calledOnce).to.be.ok;
+      });
+    });
+  });
 });