public void TestAdd()
{
int value = Generator.GetInt32();
ImmutableSortedTreeSet <int> .Builder set = ImmutableSortedTreeSet.CreateBuilder <int>();
Assert.Empty(set);
set.Add(value);
Assert.Single(set);
Assert.Equal(value, set.First());
int[] expected = { value };
int[] actual = set.ToArray();
Assert.Equal(expected, actual);
}
