Hyperion failed with "Index was out of range" in `GetDeserializedObject` when payload has Duplicate Values

[daniellittledev]

My payload contains data like this in an FSharp Record. The error goes away if the values if the values are different. Only occurs when preserve object refs is true.

    Section = Some "sd"
    SubDivision = Some "sd"

This is the exception.

$exception  {"Index was out of range. Must be non-negative and less than the size of the collection.\r\nParameter name: index"} System.ArgumentOutOfRangeException

Here is the line that fails.

public class DeserializerSession
{
    ////
    public object GetDeserializedObject(int id)
    {
        return _objectById[id]; // <- here
    }
    ////

Stack Trace

>   Hyperion.dll!Hyperion.DeserializerSession.GetDeserializedObject(int id = 14) Line 66    C#
    Hyperion.dll!Hyperion.ValueSerializers.ObjectReferenceSerializer.ReadValue(System.IO.Stream stream = {System.IO.MemoryStream}, Hyperion.DeserializerSession session = {Hyperion.DeserializerSession}) Line 34   C#
    Hyperion.dll!Hyperion.Extensions.StreamEx.ReadObject(System.IO.Stream stream = {System.IO.MemoryStream}, Hyperion.DeserializerSession session = {Hyperion.DeserializerSession}) Line 172    C#

[tvjames]

Here's a failing test in F#, it looks like the root cause is the inclusion of the F# Map type in the Header type of the Payload record.

type Header = {
    Properties: Map<int,int>;
}

type Payload<'t> = 
    {
        Header: Header;
        Value: 't
    }
    override this.ToString() =
        "Envelope: " + this.Value.ToString()

type InnerType = {
    OneField : string option
    TwoField : string option 
}
type OuterType = {
    Something : InnerType
    FirstField : string option
    SecondField : string option 
    ThirdField : string option 
}

let inner = {
    OneField = Some "value"
    TwoField = Some "value"
}

let toSerialise = {
    Header = { Properties = Map.empty; }
    Value = inner
}

toSerialise |> Dump |> ignore 

let options = Hyperion.SerializerOptions(preserveObjectReferences = true)
let serialiser = Hyperion.Serializer(options)

let ``run test`` = 
    use inbound = new MemoryStream()
    serialiser.Serialize(toSerialise, inbound)
    inbound.Flush()

    use outbound = new MemoryStream(inbound.ToArray())
    let result = serialiser.Deserialize outbound

    result

``run test`` |> Dump |> ignore 

Ran in LinqPad, using the latest Hyperion from nuget