Unit testing extension for equality testing

Question

I have created an extension for unit-testing my own equality implementations. Is it a good approach in general to have such extensions for unit testing? What unit-testing extensions do you use?

public static class EqualityExtensions
 {
 /// <summary>
 /// Checks that all variations Equals method conforms to equality by properties
 /// </summary>
 /// <typeparam name="T"></typeparam>
 /// <param name="variations"></param>
 /// <param name="propertyAccessors">Property accessors specifying which properties contribute to equality</param>
 /// <returns>True, if all instances from a set conform to property equality</returns>
 /// <example>
 /// Assert.IsTrue(from name in new[] {"foo","bar"} from count in new[] {1,2} select new MyClass{Name=name,Count=count}).ConformToPropertyEquality(x=>x.Name,x=>x.Count))
 /// </example>
 public static bool ConformToPropertyEquality<T>(this IEnumerable<T> variations, params Func<T, object>[] propertyAccessors)
 {
 var propertyComparisions =
 from lhs in variations
 from rhs in variations
 select
 Equals(
 (from comparator in propertyAccessors select Equals(comparator(lhs), comparator(rhs))).All(c => c),
 Equals(lhs, rhs)
 );
 return propertyComparisions.All(p => p);
 }
 }

Answer 1

It's perfectly OK. As an example SharpTestEx is a whole library with such an extensions.