public void CalculateSHA512_ReturnsCorrectHash_AnyTextGiven(string text, string expResult)
        {
            EncryptionManager instance = new EncryptionManager();

            Assert.AreEqual(expResult, instance.CalculateSHA512(text));
        }
        public void CalculateSHA512_ThrowsException_EmptyStringGiven()
        {
            EncryptionManager instance = new EncryptionManager();

            Assert.Throws <ArgumentException>(() => instance.CalculateSHA512(""));
        }