JsonRpcEventSource.GetArgumentsString may throw exceptions, causing failures while verbose logging

[AArnott]

As reported in devdiv-1600609, we have errors with this message coming from StreamJsonRpc:

Deserializing JSON-RPC argument with name "" and position 1 to type "" failed: Failed to deserialize System.Object value.

The message itself comes from the JsonMessageFormatter:
https://github.com/AArnott/vs-streamjsonrpc/blob/39a07107ae2a2fcc0a4846a946b2489fb4197ad1/src/StreamJsonRpc/JsonMessageFormatter.cs#L1036-L1042
and the MessagePackFormatter:
https://github.com/AArnott/vs-streamjsonrpc/blob/39a07107ae2a2fcc0a4846a946b2489fb4197ad1/src/StreamJsonRpc/MessagePackFormatter.cs#L2460-L2466

This lack of detail (e.g. no argument name nor type hint) makes triaging bug reports very difficult. This lack of detail appears from code inspection to only come from JsonRpcEventSource.GetArgumentsString here:

vs-streamjsonrpc/src/StreamJsonRpc/JsonRpcEventSource.cs

Line 294 in 39a0710

if (request.TryGetArgumentByNameOrIndex(null, i, null, out object? value))

With a similarly useless but slightly different message coming from a few lines further down:

vs-streamjsonrpc/src/StreamJsonRpc/JsonRpcEventSource.cs

Line 320 in 39a0710

if (request.TryGetArgumentByNameOrIndex(key, -1, null, out object? value))

This GetArgumentsString is only called from a few places in the JsonRpc class, all within a check for Verbose logging being enabled. In fact, the GetArgumentsString method itself is only meant for logging the arguments. But evidently that attempt to represent the arguments as a string fails, and throws an exception, leading to the failure of the overall scenario.

We really shouldn't be failing the scenario for sake of failing to log. Let's make logging more resilient!

[AArnott]

The "Failed to deserialize System.Object value" part of the error doesn't appear in Newtonsoft.Json as far as I can tell. It does appear in messagepack however, so in attempting to repro this, I think we should try the MessagePackFormatter.

[AArnott]

In fact, here is more info from the exception thrown:

StreamJsonRpc.RemoteInvocationException: Deserializing JSON-RPC argument with name "" and position 1 to type "" failed: Failed to deserialize System.Object value.
   at StreamJsonRpc.JsonRpc.d__143`1.MoveNext()
--- End of stack trace from previous location where exception was thrown ---
   at System.Runtime.ExceptionServices.ExceptionDispatchInfo.Throw()
   at System.Runtime.CompilerServices.TaskAwaiter.HandleNonSuccessAndDebuggerNotification(Task task)
   at Microsoft.CodeAnalysis.Remote.BrokeredServiceConnection`1.d__16`1.MoveNext()
RPC server exception:
StreamJsonRpc.RpcArgumentDeserializationException: Deserializing JSON-RPC argument with name "" and position 1 to type "" failed: Failed to deserialize System.Object value.
 ---> MessagePack.MessagePackSerializationException: Failed to deserialize System.Object value.
 ---> MessagePack.MessagePackSerializationException: Invalid primitive bytes.
      at MessagePack.Formatters.PrimitiveObjectFormatter.Deserialize(MessagePackReader& reader, MessagePackSerializerOptions options)
      at MessagePack.Formatters.PrimitiveObjectFormatter.Deserialize(MessagePackReader& reader, MessagePackSerializerOptions options)
      at MessagePack.Formatters.PrimitiveObjectFormatter.DeserializeMap(MessagePackReader& reader, Int32 length, MessagePackSerializerOptions options)
      at MessagePack.Formatters.PrimitiveObjectFormatter.Deserialize(MessagePackReader& reader, MessagePackSerializerOptions options)
      at MessagePack.Formatters.PrimitiveObjectFormatter.Deserialize(MessagePackReader& reader, MessagePackSerializerOptions options)
      at MessagePack.MessagePackSerializer.Deserialize[T](MessagePackReader& reader, MessagePackSerializerOptions options)
   --- End of inner exception stack trace ---
      at MessagePack.MessagePackSerializer.Deserialize[T](MessagePackReader& reader, MessagePackSerializerOptions options)
      at StreamJsonRpc.MessagePackFormatter.JsonRpcRequest.TryGetArgumentByNameOrIndex(String name, Int32 position, Type typeHint, Object& value)
   --- End of inner exception stack trace ---
      at StreamJsonRpc.MessagePackFormatter.JsonRpcRequest.TryGetArgumentByNameOrIndex(String name, Int32 position, Type typeHint, Object& value)
      at StreamJsonRpc.JsonRpcEventSource.GetArgumentsString(JsonRpcRequest request)
      at StreamJsonRpc.JsonRpc.d__158.MoveNext()