public function testAddAndGetHelper() { $new_helper = $this->getMockBuilder(Helper\InterfaceHelper::class)->getMock(); $this->object->addHelper('test_helper', $new_helper); $this->assertSame($new_helper, $this->object->getHelper('test_helper')); $this->assertSame($new_helper, $this->object->helper('test_helper')); $this->assertInstanceOf(Helper\InterfaceHelper::Class, $this->object->getHelper('test_helper')); }