nunit Make new constraint usable in a fluent context


Example

We're going to integrate the AlmostEqualToConstraint with the fluent NUnit interfaces, specifically the Is one. We'll need to extend the NUnit provided Is and use that throughout our code.

public class Is : NUnit.Framework.Is
{
    public static AlmostEqualToConstraint AlmostEqualTo(int expected, int percentageTolerance = 5)
    {
        return new AlmostEqualToConstraint(expected, percentageTolerance);
    }
}