void AssertNull <T>(IDbTypeResolver sut)
        {
            var result = sut.TryResolve(typeof(T));

            Assert.AreEqual(null, result);
        }
        void AssertEqual <T>(IDbTypeResolver sut, DbType expected)
        {
            var result = sut.TryResolve(typeof(T));

            Assert.AreEqual(expected, result);
        }