public void TestComparerEquality()
{
Func <int, int> f = i => - i;
TestEquality(Comparers.Create(f), Comparers.Create(f), Comparers.Create((int i) => i.ToString()));
TestEquality(Comparers.Reverse <int>(), Comparers.Reverse <int>(), Comparers.Create((int i) => i.ToString()).Reverse());
var first = Comparers.Create((string s) => s.Length);
var second = Comparers.Create((string s) => s[0]);
TestEquality(first.ThenBy(second), first.ThenBy(second), second.ThenBy(first));
TestEquality(Comparers.GetSequenceComparer <string>(), Comparers.GetSequenceComparer(Comparer <string> .Default), Comparers.GetSequenceComparer(StringComparer.OrdinalIgnoreCase));
}
public void TestSequenceComparer()
{
Assert.Same(Comparers.GetSequenceComparer <int>(), Comparers.GetSequenceComparer <int>());
Assert.Same(Comparers.GetSequenceComparer <int>(), Comparers.GetSequenceComparer(Comparer <int> .Default));
var sequence = new[] { new[] { 1, 2, 3 }, new[] { 1, 1, 5 }, new[] { 1, 2, 1 } };
sequence.OrderBy(i => i, Comparers.GetSequenceComparer <int>())
.Select(a => string.Join(",", a))
.SequenceShouldEqual(new[] { "1,1,5", "1,2,1", "1,2,3" });
sequence.OrderBy(i => i, Comparers.GetSequenceComparer(Comparer <int> .Default.Reverse()))
.Select(a => string.Join(",", a))
.SequenceShouldEqual(new[] { "1,2,3", "1,2,1", "1,1,5" });
Math.Sign(Comparers.GetSequenceComparer <int>().Compare(Empty.Array <int>(), new[] { 1 }))
.ShouldEqual(-1);
}