public void BinarySearch_NullList_ThrowsNullReferenceException()
{
// Arrange
Comparer <int> comparer = Comparer <int> .Default;
// Act & Assert
Assert.Throws <NullReferenceException>(() => IReadOnlyListExtensions.BinarySearch(null, 1, comparer));
}
public void IndexOf_ValueAppearsMultipleTimes_CorrectlyReturnsFirstInstance()
{
// Arrange
IReadOnlyList <int> list = new[] { 2, 4, 6, 8, 4 };
// Act
int index = IReadOnlyListExtensions.IndexOf(list, 4);
// Assert
Assert.Equal(1, index);
}
public void IndexOf_ValueNotInList_CorrectlyReturnsNegativeOne()
{
// Arrange
IReadOnlyList <int> list = new[] { 2, 4, 6, 8 };
// Act
int index = IReadOnlyListExtensions.IndexOf(list, 1);
// Assert
Assert.Equal(-1, index);
}
public void IndexOf_ValueInList_CorrectlyReturnsIndex()
{
// Arrange
IReadOnlyList <int> list = new[] { 6, 4, 1, 8 };
// Act
int index = IReadOnlyListExtensions.IndexOf(list, 1);
// Assert
Assert.Equal(2, index);
}
public void BinarySearch_OddNumberOfElements_CorrectlyMatchesListImplementation()
{
// Arrange
// 6 elements total
const int minFillIndexInclusive = 1;
const int maxFillIndexInclusive = 5;
Comparer <int> comparer = Comparer <int> .Default;
List <int> list = new List <int>();
for (int i = minFillIndexInclusive; i <= maxFillIndexInclusive; i++)
{
list.Add(2 * i); // multiplying each entry by 2 to make sure there are gaps
}
// Act & Assert
for (int i = minFillIndexInclusive - 1; i <= maxFillIndexInclusive + 1; i++)
{
Assert.Equal(list.BinarySearch(i, comparer), IReadOnlyListExtensions.BinarySearch(list, i, comparer));
Assert.Equal(list.BinarySearch(i + 1, comparer), IReadOnlyListExtensions.BinarySearch(list, i + 1, comparer));
}
}
public void IndexOf_NullList_ThrowsNullReferenceException()
{
// Arrange, Act, and Assert
Assert.Throws <NullReferenceException>(() => IReadOnlyListExtensions.IndexOf(null, 1));
}
