public void It_should_generate_only_unique_ids_even_when_time_goes_backward()
{
const long sequenceMask = -1L ^ (-1L << 12);
var worker = new StaticTimeWorker(0, 0);
// reported at https://github.com/twitter/snowflake/issues/6
// first we generate 2 ids with the same time, so that we get the sequqence to 1
Assert.That(worker.Sequence, Is.EqualTo(0));
Assert.That(worker.Time, Is.EqualTo(1));
var id1 = worker.NextId();
Assert.That(id1 >> 22, Is.EqualTo(1));
Assert.That(id1 & sequenceMask, Is.EqualTo(0));
Assert.That(worker.Sequence, Is.EqualTo(0));
Assert.That(worker.Time, Is.EqualTo(1));
var id2 = worker.NextId();
Assert.That(id2 >> 22, Is.EqualTo(1));
Assert.That(id2 & sequenceMask, Is.EqualTo(1));
//then we set the time backwards
worker.Time = 0;
Assert.That(worker.Sequence, Is.EqualTo(1));
Assert.Throws <InvalidSystemClock>(() => worker.NextId());
Assert.That(worker.Sequence, Is.EqualTo(1)); // this used to get reset to 0, which would cause conflicts
worker.Time = 1;
var id3 = worker.NextId();
Assert.That(id3 >> 22, Is.EqualTo(1));
Assert.That(id3 & sequenceMask, Is.EqualTo(2));
}
public void It_should_generate_only_unique_ids_even_when_time_goes_backward()
{
const long sequenceMask = -1L ^ (-1L << 12);
var worker = new StaticTimeWorker(0, 0);
// reported at https://github.com/twitter/snowflake/issues/6
// first we generate 2 ids with the same time, so that we get the sequqence to 1
Assert.That(worker.Sequence, Is.EqualTo(0));
Assert.That(worker.Time, Is.EqualTo(1));
var id1 = worker.NextId();
Assert.That(id1 >> 22, Is.EqualTo(1));
Assert.That(id1 & sequenceMask, Is.EqualTo(0));
Assert.That(worker.Sequence, Is.EqualTo(0));
Assert.That(worker.Time, Is.EqualTo(1));
var id2 = worker.NextId();
Assert.That(id2 >> 22, Is.EqualTo(1));
Assert.That(id2 & sequenceMask, Is.EqualTo(1));
//then we set the time backwards
worker.Time = 0;
Assert.That(worker.Sequence, Is.EqualTo(1));
Assert.Throws<InvalidSystemClock>(() => worker.NextId());
Assert.That(worker.Sequence, Is.EqualTo(1)); // this used to get reset to 0, which would cause conflicts
worker.Time = 1;
var id3 = worker.NextId();
Assert.That(id3 >> 22, Is.EqualTo(1));
Assert.That(id3 & sequenceMask, Is.EqualTo(2));
}