public void TestThenByComparerPreserved()
{
var sequence = new[]
{
new { A = "2", B = "0" },
new { A = "1", B = "5" },
new { A = "2", B = "2" },
new { A = "1", B = "3" },
new { A = "1", B = "4" },
new { A = "2", B = "1" },
};
var comparer = new ComparerFunc <string>((a, b) => int.Parse(a).CompareTo(int.Parse(b)));
var resultA1 = sequence.OrderBy(x => x.A, comparer, OrderByDirection.Ascending)
.ThenBy(y => y.B, comparer, OrderByDirection.Ascending);
var resultA2 = sequence.OrderBy(x => x.A, comparer)
.ThenBy(y => y.B, comparer);
// ensure both produce the same order
Assert.IsTrue(resultA1.SequenceEqual(resultA2));
var resultB1 = sequence.OrderBy(x => x.A, comparer, OrderByDirection.Ascending)
.ThenBy(y => y.B, comparer, OrderByDirection.Descending);
var resultB2 = sequence.OrderBy(x => x.A, comparer)
.ThenByDescending(y => y.B, comparer);
// ensure both produce the same order
Assert.IsTrue(resultB1.SequenceEqual(resultB2));
}
public void TestRankCustomComparer()
{
const int count = 10;
var ordinals = Enumerable.Range(1, count);
var sequence = ordinals.Select(x => new DateTime(2010, x, 20 - x));
// invert the CompareTo operation to Rank in reverse order (ascening to descending)
var resultA = sequence.AsTestingSequence().Rank(ComparerFunc <DateTime> .As((a, b) => - a.CompareTo(b)));
var resultB = sequence.AsTestingSequence().RankBy(x => x.Day, ComparerFunc <int> .As((a, b) => - a.CompareTo(b)));
Assert.IsTrue(resultA.SequenceEqual(ordinals));
Assert.IsTrue(resultB.SequenceEqual(ordinals.Reverse()));
}
public void TestOrderByComparerPreserved()
{
var sequence = Enumerable.Range(1, 100);
var sequenceAscending = sequence.Select(x => x.ToString());
var sequenceDescending = sequenceAscending.Reverse();
var comparer = new ComparerFunc <string>((a, b) => int.Parse(a).CompareTo(int.Parse(b)));
var resultAsc1 = sequenceAscending.OrderBy(x => x, comparer, OrderByDirection.Descending);
var resultAsc2 = sequenceAscending.OrderByDescending(x => x, comparer);
// ensure both order by operations produce identical results
Assert.IsTrue(resultAsc1.SequenceEqual(resultAsc2));
// ensure comparer was applied in the order by evaluation
Assert.IsTrue(resultAsc1.SequenceEqual(sequenceDescending));
var resultDes1 = sequenceDescending.OrderBy(x => x, comparer, OrderByDirection.Ascending);
var resultDes2 = sequenceDescending.OrderBy(x => x, comparer);
// ensure both order by operations produce identical results
Assert.IsTrue(resultDes1.SequenceEqual(resultDes2));
// ensure comparer was applied in the order by evaluation
Assert.IsTrue(resultDes1.SequenceEqual(sequenceAscending));
}