public void NormalComparer()
{
var original = StringComparer.Ordinal;
var subject = new ReverseComparer <string>(original);
Assert.AreEqual(original.Compare("x", "y"), subject.Compare("y", "x"));
Assert.AreEqual(0, subject.Compare("x", "x"));
}
public void Simple()
{
var comparer = new ReverseComparer<int>();
Assert.AreEqual(comparer.Compare(2, 3), 1);
Assert.AreEqual(comparer.Compare(3, 2), -1);
Assert.AreEqual(comparer.Compare(0, 0), 0);
Assert.AreEqual(comparer.Compare(0, 1), 1);
Assert.AreEqual(comparer.Compare(1, 0), -1);
}
public void Simple()
{
var comparer = new ReverseComparer <int>();
Assert.AreEqual(comparer.Compare(2, 3), 1);
Assert.AreEqual(comparer.Compare(3, 2), -1);
Assert.AreEqual(comparer.Compare(0, 0), 0);
Assert.AreEqual(comparer.Compare(0, 1), 1);
Assert.AreEqual(comparer.Compare(1, 0), -1);
}
public void ReverseComparerReturnsZeroWhenFirstItemEqualsSecondItem()
{
var comparer = new ReverseComparer <int>(Comparer <int> .Default);
int first = 1;
int second = 1;
int result = comparer.Compare(first, second);
Assert.AreEqual(0, result);
}
public void ReverseComparerReturnsPositiveOneWhenFirstItemIsLessThanSecondItem()
{
var comparer = new ReverseComparer <int>(Comparer <int> .Default);
int first = 1;
int second = 2;
int result = comparer.Compare(first, second);
Assert.AreEqual(1, result);
}
public void CustomComparer_LessThan()
{
// Arrange
var comparer = new CustomIntComparer();
var reversedComparer = new ReverseComparer <int>(comparer);
// Act-Assert (Precondition)
Assert.Equal(-2, comparer.Compare(1, 2));
// Act-Assert
Assert.Equal(2, reversedComparer.Compare(1, 2));
}
public void ReverseDefaultIntegerComparer_LessThan()
{
// Arrange
var comparer = Comparer <int> .Default;
var reversedComparer = new ReverseComparer <int>(comparer);
// Act-Assert (Precondition)
Assert.Equal(-1, comparer.Compare(1, 2));
// Act-Assert
Assert.Equal(1, reversedComparer.Compare(1, 2));
}
public void ReverseDefaultStringComparer_WithNull_GreaterThan()
{
// Arrange
var comparer = Comparer <string> .Default;
var reversedComparer = new ReverseComparer <string>(comparer);
// Act-Assert (Precondition)
Assert.Equal(1, comparer.Compare("A", null));
// Act-Assert
Assert.Equal(-1, reversedComparer.Compare("A", null));
}
public void ReverseDefaultStringComparer_WithNull_LessEqual()
{
// Arrange
var comparer = Comparer <string> .Default;
var reversedComparer = new ReverseComparer <string>(comparer);
// Act-Assert (Precondition)
Assert.Equal(0, comparer.Compare(null, null));
// Act-Assert
Assert.Equal(0, reversedComparer.Compare(null, null));
}
public void CustomComparer_Limits_GreaterThan()
{
// Arrange
var comparer = new CustomIntComparerLimits();
var reversedComparer = new ReverseComparer <int>(comparer);
// Act-Assert (Precondition)
Assert.Equal(int.MaxValue, comparer.Compare(2, 1));
// Act-Assert
Assert.Equal(int.MinValue, reversedComparer.Compare(2, 1));
}
public void Test_ReverseComparer_EqualTo()
{
// Arrange.
IComparer <int> baseComparer = Comparer <int> .Default;
IComparer <int> reverseComparer = new ReverseComparer <int>(baseComparer);
// Act.
int result = baseComparer.Compare(2, 2);
int reversedResult = reverseComparer.Compare(2, 2);
// Assert.
Assert.Equal(result, reversedResult);
Assert.Equal(0, result);
Assert.Equal(0, reversedResult);
}
public void Test_ReverseComparer_GreaterThan()
{
// Arrange.
IComparer <int> baseComparer = Comparer <int> .Default;
IComparer <int> reverseComparer = new ReverseComparer <int>(baseComparer);
// Act.
int result = baseComparer.Compare(2, 1);
int reversedResult = reverseComparer.Compare(2, 1);
// Assert.
Assert.NotEqual(result, reversedResult);
Assert.True(result > 0);
Assert.True(reversedResult < 0);
}