public function test__equals()
{
$a = Clock::tick(Clock::system(self::PARIS()), Duration::ofMillis(500));
$b = Clock::tick(Clock::system(self::PARIS()), Duration::ofMillis(500));
$this->assertEquals($a->equals($a), true);
$this->assertEquals($a->equals($b), true);
$this->assertEquals($b->equals($a), true);
$this->assertEquals($b->equals($b), true);
$c = Clock::tick(Clock::system(self::MOSCOW()), Duration::ofMillis(500));
$this->assertEquals($a->equals($c), false);
$d = Clock::tick(Clock::system(self::PARIS()), Duration::ofMillis(499));
$this->assertEquals($a->equals($d), false);
$this->assertEquals($a->equals(null), false);
$this->assertEquals($a->equals("other type"), false);
$this->assertEquals($a->equals(Clock::systemUTC()), false);
}