public function testCaptcha($expectArray = [])
{
/* setup */
$form = new Html\Form($this->_registry, $this->_language);
$form->init(null, ['captcha' => true]);
$form->captcha($expectArray['type']);
/* actual */
$actual = $form->render();
/* compare */
$this->assertStringStartsWith($expectArray['start'], $actual);
$this->assertStringEndsWith($expectArray['end'], $actual);
}