public void Backward()
{
var log = new OpDataPersister(Cfg4Mb);
log.Append(ToBytes(1));
log.Append(ToBytes(2));
log.Append(ToBytes(3));
log.Append(ToBytes(4));
log.Append(ToBytes(5));
var iter = log.Backward().GetEnumerator(); ;
iter.MoveNext();
Assert.That(ToInt(iter.Current.Payload), Is.EqualTo(5));
iter.MoveNext();
Assert.That(ToInt(iter.Current.Payload), Is.EqualTo(4));
iter.MoveNext();
Assert.That(ToInt(iter.Current.Payload), Is.EqualTo(3));
iter.MoveNext();
Assert.That(ToInt(iter.Current.Payload), Is.EqualTo(2));
iter.MoveNext();
Assert.That(ToInt(iter.Current.Payload), Is.EqualTo(1));
}
public void Backward_a_slice()
{
var log = new OpDataPersister(Cfg4Mb);
log.Append(ToBytes(1));
log.Append(ToBytes(2));
log.Append(ToBytes(3));
log.Append(ToBytes(4));
log.Append(ToBytes(5));
var items = new List<int>();
foreach (var v in log.Backward(int.MaxValue, 2))
items.Add(BitConverter.ToInt32(v.Payload, 0));
Assert.That(items[0], Is.EqualTo(5));
Assert.That(items[1], Is.EqualTo(4));
Assert.That(items.Count, Is.EqualTo(2));
}
public void Backward_from_position()
{
var log = new OpDataPersister(Cfg4Mb);
log.Append(ToBytes(14));
log.Append(ToBytes(2));
var idx = log.Append(ToBytes(34));
log.Append(ToBytes(234));
log.Append(ToBytes(455));
var iter = log.Backward(idx).GetEnumerator(); ;
iter.MoveNext();
Assert.That(ToInt(iter.Current.Payload), Is.EqualTo(34));
iter.MoveNext();
Assert.That(ToInt(iter.Current.Payload), Is.EqualTo(2));
iter.MoveNext();
Assert.That(ToInt(iter.Current.Payload), Is.EqualTo(14));
Assert.That(iter.MoveNext(), Is.False);
}
public void ListBackwardTest()
{
var wr = new OpDataPersister(Cfg4K);
for (int i = 0; i < 100; i++)
wr.Append(BitConverter.GetBytes(i));
wr.Dispose();
var rd = new OpDataPersister(Cfg4K);
long prev = long.MaxValue;
foreach (var op in rd.Backward())
{
var position = op.Position;
Assert.That(position, Is.LessThan(prev));
Console.WriteLine(op.Position + " " + BitConverter.ToInt32(op.Payload, 0));
prev = position;
}
}
