How can I create unit tests involving collections in c#?

I have a number of methods in C# which return various collections which I wish to test. I would like to use as few test APIs as possible - performance is not important. A typical example is: ``` HashSet<string> actualSet = MyCreateSet(); string[] expectedArray = new string[]{"a", "c", "b"}; MyAssertAreEqual(expectedArray, actualSet); ``` //... ``` void MyAssertAreEqual(string[] expected, HashSet<string> actual) { HashSet<string> expectedSet = new HashSet<string>(); foreach {string e in expected) { expectedSet.Add(e); } Assert.IsTrue(expectedSet.Equals(actualSet)); } ``` I am having to write a number of signatures according to whether the collections are arrays, Lists, ICollections, etc. Are there transformations which simplify this (e.g. for converting an array to a Set?). I also need to do this for my own classes. I have implemented HashCode and Equals for them. They are (mainly) subclassed from (say) MySuperClass. Is it possible to implement the functionality: ``` void MyAssertAreEqual(IEnumerable<MySuperClass> expected, IEnumerable<MySuperClass> actual); ``` such that I can call: ``` IEnumerable<MyClassA> expected = ...; IEnumerable<MyClassA> actual = ...; MyAssertAreEqual(expected, actual); ``` rather than writing this for every class