MonoTouch: JsonDeserializer causes internal consistency error

[nicwise]

Hi

I've been trying to track down a problem in my MonoTouch app, which I updated to 103.1 yesterday.

It appears to be caused by this change:

85d4693

Specifically:

    private IList BuildList(Type type, object parent)
    {
        var list = (IList)Activator.CreateInstance(type);
        //var listType = type.GetInterfaces().First(x => x.GetGenericTypeDefinition() == typeof(IList<>));
        //var itemType = listType.GetGenericArguments()[0];
        var itemType = type.GetGenericArguments()[0];

(the 2 commented lines are the current code. The line after is what it USED to be)

The MonoTouch bug case is here:

https://bugzilla.xamarin.com/show_bug.cgi?id=6031

I'm not sure of the repercussions of the change above, but it makes my code work, where before it was crashing around 75% of the time.

Is there another way to do it? it's the First(x => x.GetGenericTypeDefinition()) which is causing the issue.

Thanks.

[nicwise]

I just unrolled the LINQ bit (.First(x => ....)) and it's not - it's the call to GetGenericTypeDefinition which is the problem. Still waiting on some comments from Xamarin, tho it IS the weekend.

[ayoung]

Having worked with MonoTouch before, I wouldn't say its unlikely to be an MT issue. Please keep us updated on the issue on our Google Groups page. I'm closing this issue.

[nicwise]

Thanks Andrew. Any comments on why that line of code changed? maybe @petejohanson knows :)

I'll ask on the list.

[ayoung]

Yeah. I think the reason was because if you had a class like

class ProductList : List

It wouldn't deserialize properly -- it would just set whatever property it
was to null. The deserializer wasn't looking up the inheritance chain to
find the right type. See this pull request for more info
#236

On Mon, Jul 9, 2012 at 1:55 PM, Nic Wise <
reply@reply.github.com

wrote:

Thanks Andrew. Any comments on why that line of code changed? maybe
@petejohanson knows :)

I'll ask on the list.

---

Reply to this email directly or view it on GitHub:
#293 (comment)

[nicwise]

Thanks @ayoung I'll follow it up with the Xamarin folks - most likely it'll be a AOT-type bug.... if I can work out a work around (which isn't just rolling the change back) I'll submit a pull request with a conditional compile thinggie in it.

[nicwise]

Nope, it was something else. PR submitted for your perusal :)

#295