public static void ToFlickrBase58String_ThrowsArgumentOutOfRangeException_ForNegativeInt64()
 => Assert.Throws <ArgumentOutOfRangeException>(() => Int64Encoder.ToFlickrBase58String(-1));
 public static void ToFlickrBase58String_ReturnsExpectedString(string expectedValue, long value)
 => Assert.Equal(expectedValue, Int64Encoder.ToFlickrBase58String(value));
        public static void RoundTrippingFlickrBase58Encoding_IsInvariant()
        {
            long value = 3471391110;

            Assert.Equal(value, Int64Encoder.FromFlickrBase58String(Int64Encoder.ToFlickrBase58String(value)));
        }