FluentValidation: ShouldHaveValidationErrorFor and ShouldNotHaveValidationErrorFor needs identity overload

This won’t compile in C#:

// Mock.Of refers to Moq
validator.ShouldNotHaveValidationErrorFor<Model, Model>(
                m => m,
                Mock.Of<Model>,
                "Create,CreateOrUpdate");

generates compile error:

Severity	Code	Description	Project	File	Line	Suppression State
Error	CS0121	The call is ambiguous between the following methods or properties: 'ValidationTestExtension.ShouldHaveValidationErrorFor<T, TValue>(IValidator<T>, Expression<Func<T, TValue>>, TValue, string)' and 'ValidationTestExtension.ShouldHaveValidationErrorFor<T, TValue>(IValidator<T>, Expression<Func<T, TValue>>, T, string)'	Tests	C:\source\ModelValidatorTests.cs	86	Active

I believe we need an overload to express the Identity function relationship:

    public static class ValidationTestExtension
    {
        public static IEnumerable<ValidationFailure> ShouldHaveValidationErrorFor<T>(this IValidator<T> validator, Expression<Func<T, T>> expression, T value, string ruleSet)
            where T : class, new()
        {
            T instance = Activator.CreateInstance<T>();
            return validator.TestValidate<T>(instance, ruleSet).ShouldHaveError<T, T>();
        }
    }

This is useful when writing validations that involve multiple properties.