Fix: Sync Hook not called (#6681)

* Update hooks.js

Fixed error where `return` was called inside of a for loop. 
This prevented execution of more than one synchronous hook.

* Added tests for before/afterInit and before/afterDefine hooks

* sooo many new lines 🔥

changelog.md

 # Future
+- [FIXED] Issue with sync hooks (before/afterInit, before/afterDefine) [#6680](https://github.com/sequelize/sequelize/issues/6680)
 - [FIXED] MSSQL handle large bulk inserts #6866
 - [FIXED] describeTable returns a wrong value for primaryKey [#5756] (https://github.com/sequelize/sequelize/issues/5756)
 - [FIXED] MSSQL LIMIT IN UPDATE [#6636](https://github.com/sequelize/sequelize/issues/6636)

lib/hooks.js

@@ -106,7 +106,7 @@ const Hooks = {
         }
 
         debug(`running hook(sync) ${hookType}`);
-        return hook.apply(this, hookArgs);
+        hook.apply(this, hookArgs);
       }
       return;
     }

test/unit/hooks.test.js

@@ -302,4 +302,54 @@ describe(Support.getTestDialectTeaser('Hooks'), function() {
       return expect(this.Model.runHooks('beforeCreate')).to.be.rejectedWith('Forbidden');
     });
   });
+
+  describe('sync hooks', function() {
+    beforeEach(function () {
+      this.hook1 = sinon.spy();
+      this.hook2 = sinon.spy();
+      this.hook3 = sinon.spy();
+      this.hook4 = sinon.spy();
+    });
+
+    it('runs all beforInit/afterInit hooks', function() {
+      Support.Sequelize.addHook('beforeInit', 'h1', this.hook1);
+      Support.Sequelize.addHook('beforeInit', 'h2', this.hook2);
+      Support.Sequelize.addHook('afterInit', 'h3', this.hook3);
+      Support.Sequelize.addHook('afterInit', 'h4', this.hook4);
+
+      Support.createSequelizeInstance();
+
+      expect(this.hook1).to.have.been.calledOnce;
+      expect(this.hook2).to.have.been.calledOnce;
+      expect(this.hook3).to.have.been.calledOnce;
+      expect(this.hook4).to.have.been.calledOnce;
+
+      // cleanup hooks on Support.Sequelize
+      Support.Sequelize.removeHook('beforeInit', 'h1');
+      Support.Sequelize.removeHook('beforeInit', 'h2');
+      Support.Sequelize.removeHook('afterInit', 'h3');
+      Support.Sequelize.removeHook('afterInit', 'h4');
+
+      Support.createSequelizeInstance();
+
+      // check if hooks were removed
+      expect(this.hook1).to.have.been.calledOnce;
+      expect(this.hook2).to.have.been.calledOnce;
+      expect(this.hook3).to.have.been.calledOnce;
+      expect(this.hook4).to.have.been.calledOnce;
+    });
+
+    it('runs all beforDefine/afterDefine hooks', function() {
+      const sequelize = Support.createSequelizeInstance();
+      sequelize.addHook('beforeDefine', this.hook1);
+      sequelize.addHook('beforeDefine', this.hook2);
+      sequelize.addHook('afterDefine', this.hook3);
+      sequelize.addHook('afterDefine', this.hook4);
+      sequelize.define('Test', {});
+      expect(this.hook1).to.have.been.calledOnce;
+      expect(this.hook2).to.have.been.calledOnce;
+      expect(this.hook3).to.have.been.calledOnce;
+      expect(this.hook4).to.have.been.calledOnce;
+    });
+  });
 });