public void Test_Tail()
{
var writer = new SliceWriter(64);
var slice = writer.Tail(0);
Assert.That(slice.Count, Is.EqualTo(0));
Assert.That(slice.Offset, Is.EqualTo(0));
//note: slice.Array is not guaranteed to be equal to writer.Buffer
Assert.That(() => writer.Head(1), Throws.InstanceOf <ArgumentOutOfRangeException>());
writer.WriteBytes(Slice.FromString("hello world!"));
slice = writer.Tail(6);
Assert.That(slice.Array, Is.SameAs(writer.Buffer));
Assert.That(slice.Offset, Is.EqualTo(6));
Assert.That(slice.Count, Is.EqualTo(6));
Assert.That(slice.ToStringAscii(), Is.EqualTo("world!"));
slice = writer.Tail(12);
Assert.That(slice.Array, Is.SameAs(writer.Buffer));
Assert.That(slice.Offset, Is.EqualTo(0));
Assert.That(slice.Count, Is.EqualTo(12));
Assert.That(slice.ToStringAscii(), Is.EqualTo("hello world!"));
Assert.That(() => writer.Tail(13), Throws.InstanceOf <ArgumentOutOfRangeException>());
Assert.That(() => writer.Tail(-1), Throws.InstanceOf <ArgumentOutOfRangeException>());
writer.WriteBytes(Slice.FromString("foo"));
slice = writer.Tail(3);
Assert.That(slice.Array, Is.SameAs(writer.Buffer));
Assert.That(slice.Offset, Is.EqualTo(12));
Assert.That(slice.Count, Is.EqualTo(3));
Assert.That(slice.ToStringAscii(), Is.EqualTo("foo"));
slice = writer.Tail(15);
Assert.That(slice.Array, Is.SameAs(writer.Buffer));
Assert.That(slice.Offset, Is.EqualTo(0));
Assert.That(slice.Count, Is.EqualTo(15));
Assert.That(slice.ToStringAscii(), Is.EqualTo("hello world!foo"));
Assert.That(() => writer.Tail(16), Throws.InstanceOf <ArgumentOutOfRangeException>());
}