public function owner()
{
$this->assertEquals(vfsStream::getCurrentUser(), $this->dir->getUser());
$this->assertTrue($this->dir->isOwnedByUser(vfsStream::getCurrentUser()));
$this->assertSame($this->dir, $this->dir->chown(vfsStream::OWNER_USER_1));
$this->assertEquals(vfsStream::OWNER_USER_1, $this->dir->getUser());
$this->assertTrue($this->dir->isOwnedByUser(vfsStream::OWNER_USER_1));
}