public void CalculatesExpectedUsernameStringFromHash(long hash, string expectedUsername)
        {
            var actualUsername = UsernameHelper.HashToUsername(hash);

            Assert.Equal(expectedUsername, actualUsername);
        }
        public void CalculatesExpectedHashFromUsernameString(string username, long expectedHash)
        {
            var actualHash = UsernameHelper.UsernameToHash(username);

            Assert.Equal(expectedHash, actualHash);
        }