TestSerialisationHelper.cs

using MessagePack;
using System;
using System.IO;
using System.Runtime.Serialization.Formatters.Binary;
using System.Text.Json;

namespace kx.Test.TestUtils
{
  /// <summary>
  /// A helper class for testing serialisation and de-serialisation logic 
  /// in unit-tests
  /// </summary>
  internal static class TestSerialisationHelper
  {
    /// <summary>
    /// Performs binary serialisation and de-serialisation on a specified exception.
    /// </summary>
    /// <typeparam name="T">The type of exception being tested.</typeparam>
    /// <param name="exception">The exception to be serialised and de-serialised.</param>
    /// <returns>
    /// A de-serialised instance of the exception passed. All serialisable members should match the original.
    /// </returns>
    /// <remarks>
    /// This is primarily intended to confirm custom exceptions within the DeltaApiCore 
    /// library comply to ISerialization pattern.
    /// 
    /// See https://stackoverflow.com/questions/94488/what-is-the-correct-way-to-make-a-custom-net-exception-serializable
    /// </remarks>
    public static T SerialiseAndDeserialiseException<T>(T exception)
        where T : Exception
    {
      using (var stream = new MemoryStream())
      {
        MessagePackSerializer.Serialize(stream, exception, MessagePack.Resolvers.ContractlessStandardResolver.Options);

        stream.Seek(0, 0);

        return (T)MessagePackSerializer.Deserialize<T>(stream, MessagePack.Resolvers.ContractlessStandardResolver.Options);
      }
    }
  }
}