public function testAncestor()
{
$key = new Key('foo', ['path' => [['kind' => 'thing']]]);
$key->ancestor('Hello', 'World');
$this->assertEquals(['kind' => 'Hello', 'name' => 'World'], $key->keyObject()['path'][0]);
$this->assertEquals(['kind' => 'thing'], $key->keyObject()['path'][1]);
}