public function testGetParent_GetParentOfCurrent()
{
$current = Process::current();
$current1 = Process::process($current->getPid());
$parent = $current->getParent();
$parent1 = $current1->getParent();
$this->assertInstanceOf(get_class($current), $parent);
$this->assertInternalType('int', $parent->getPid());
$this->assertEquals($parent1->getPid(), $parent->getPid());
$this->assertGreaterThan(0, $parent->getPid());
}