public function testPropsMethod()
{
$e = new Example('example/5');
$keys = array_keys($e->props());
$values = array_values($e->props());
sort($keys);
sort($values);
$this->assertEquals($keys, ['code', 'desc', 'ft', 'link', 'out']);
$this->assertEquals($values, ['1.txt 2.txt', 'Hello', 'http://najomi.org', 'lisp', 'ls']);
}