public void AttributeSafeWithInvalidArgumentsReturnsEmptyString()
        {
            var result = ExtensionMethods.AttributeSafe(null, null);

            Assert.AreEqual(string.Empty, result);

            var elem = CreateXml();

            result = elem.AttributeSafe(null);
            Assert.AreEqual(string.Empty, result);
            result = elem.AttributeSafe(string.Empty);
            Assert.AreEqual(string.Empty, result);
            result = elem.AttributeSafe("y");
            Assert.AreEqual(string.Empty, result);
        }