public void HashSetWithBuiltInComparer_HashSetContainsNotUsed()
{
IEnumerable<string> input1 = new HashSet<string>(StringComparer.OrdinalIgnoreCase) { "a" };
IEnumerable<string> input2 = new[] { "A" };
Assert.Equal(Enumerable.Empty<string>(), input1.Intersect(input2));
Assert.Equal(Enumerable.Empty<string>(), input1.Intersect(input2, null));
Assert.Equal(Enumerable.Empty<string>(), input1.Intersect(input2, EqualityComparer<string>.Default));
Assert.Equal(new[] { "a" }, input1.Intersect(input2, StringComparer.OrdinalIgnoreCase));
Assert.Equal(Enumerable.Empty<string>(), input2.Intersect(input1));
Assert.Equal(Enumerable.Empty<string>(), input2.Intersect(input1, null));
Assert.Equal(Enumerable.Empty<string>(), input2.Intersect(input1, EqualityComparer<string>.Default));
Assert.Equal(new[] { "A" }, input2.Intersect(input1, StringComparer.OrdinalIgnoreCase));
}
public void should_get_sequences_intersection()
{
var firstSequence = new[] { 1, 2, 3 };
var secondSequence = new[] { 4, 3, 5 };
IEnumerable<int> intersection = firstSequence.Intersect(secondSequence);
// please update variable value to fix the test.
IEnumerable<int> expectedIntersection = new[] { 1, 2, 3 };
Assert.Equal(expectedIntersection, intersection);
}