public void ValidateTest()
        {
            var a = new CsvRegularExpressionAttribute("^[a-zA-Z0-9]+$");

            var context = new CsvValidationContext("foo", 1, "halfAlphanumericOnly");

            Assert.IsTrue(a.Validate(context, out string _));
        }
        public void ValidateeFailureTest()
        {
            var a = new CsvRegularExpressionAttribute("^[0-9]+$");

            var context = new CsvValidationContext("foo", 1, "halfAlphanumericOnly");

            Assert.IsFalse(a.Validate(context, out string message));
            Assert.AreEqual(CsvConfig.Current.ValidationMessage.GetInvalidFormatError(context), message);
        }