Unable to serialise class with non-settable collection

[nzbart]

Microsoft mandates that classes must not expose settable collection properties. I'm not aware of any classes in the BCL that violate this rule.

Unfortunately, msgpack doesn't serialise instances that comply with this rule. JSON.NET and System.Xml.Serialization.XmlSerializer both use the Add method on the collection to support non-settable collections.

Below is a test that fails that I think should pass:

    class CompliantClass
    {
        //compliant with Microsoft guidelines at https://msdn.microsoft.com/en-us/library/dn169389%28v=vs.110%29.aspx:
        // "X DO NOT provide settable collection properties."
        public List<int> Integers { get; private set; }

        public CompliantClass()
        {
            Integers = new List<int>();
        }
    }

    //This test currently fails, but I would like it to pass
    [Test]
    public void Given_a_class_with_non_settable_list_property_When_serialised_with_msgpack_Then_no_exception_should_be_thrown()
    {
        SerializationContext.Default.GetSerializer<CompliantClass>();
    }

Is there a way to get msgpack to support this style of class?

[yfakariya]

It should be supported since *Serialization namespace had been added, so it looks like a bug. I'll try to repro and investigate this. Would you tell me about your version of msgpack and your platform(.net, winrt, xamarin.ios etc.)?

[nzbart]

I'm using the latest version on NuGet on .NET 4.5.2.

[yfakariya]

Sorry, serializer generator did not consider readonly collection typed property which has non-public setter. I'll fix in next release.

[nzbart]

Thanks!

[yfakariya]

Note: internal types are not supported, so your sample code ultimately causes TypeLoadException. I tested make your CompliantClass public.

[nzbart]

You're right. I just modified my test to better represent what I want, and noticed that it passes:

public class CompliantClass
{
    //compliant with Microsoft guidelines at https://msdn.microsoft.com/en-us/library/dn169389%28v=vs.110%29.aspx:
    // "X DO NOT provide settable collection properties."
    public List<int> Integers { get; private set; }

    public CompliantClass()
    {
        Integers = new List<int>();
    }
}

[TestFixture]
public class CompliantClassTests
{
    [Test]
    public void Given_a_class_with_non_settable_list_property_When_round_tripped_with_msgpack_Then_the_list_should_be_identical()
    {
        //Arrange
        var original = new CompliantClass();
        var values = new[] { 1, 5, 9 };
        original.Integers.AddRange(values);
        var serialiser = SerializationContext.Default.GetSerializer<CompliantClass>();
        var stream = new MemoryStream();

        //Act
        serialiser.Pack(stream, original);
        stream.Position = 0;
        var deserialised = serialiser.Unpack(stream);

        //Assert
        Assert.That(deserialised.Integers, Is.EqualTo(values));
    }
}

Did you fix the issue, or was the problem in my original test? I'm running with 0.5.9, which I notice you released yesterday.

[yfakariya]

Yes, I did and I ran yours locally too, and I decided to add another form test case in ComplexType.cs and AutoMessagePackSerializer.ttinclude to enabl
e regression tests for all generator flavors.
2246e80

Do you have any problems yet?

[nzbart]

I've upgraded to the latest NuGet package and run our unit tests. No problems identified.

Thanks for the quick turnaround!

[yfakariya]

Not at all, sorry for inconvenience.