public function testGetTypes()
{
$optionArray = array(array('value' => 'multiselect', 'label' => __('Multiple Select')), array('value' => 'select', 'label' => __('Dropdown')));
$expectedResult = ['multiselect', 'select'];
$this->inputType->expects($this->once())->method('toOptionArray')->will($this->returnValue($optionArray));
$this->assertEquals($expectedResult, $this->model->getTypes());
}