Registering an empty enum metadata array causes downstream errors

[pbirkhol-ni]

This bug is going to be short on details until I can investigate further. The measurmentlink-labview project upgraded to grpc-labview 1.0.1.1 recently and our measurements that don't use enums no longer work. The issue appears to require the following things to happen, although this is based on a very preliminary analysis:

• Calling Register Enum Metadata.vi with an empty array. This might happen when your measurement doesn't use enums.
• Downstream, calling Create And Register Server Event.vim will error.

One potential workaround is to just not call Register Enum Metadata.vi when you don't have any enum metadata. I haven't tried this, but it could be a valid workaround. That being said, this issue should get fixed.

AB#2527812

[pbirkhol-ni]

If I don't call Register Enum Metadata.vi when there is no metadata to register, that fixes the error. However, one of our examples uses enum values that don't seem to be compatible with grpc-labview.

I think what needs to happen is that we need the ability to use LabVIEW enums without using grpc-labview enums. Instead, grpc-labview will just treat them as numbers. Then we don't have to play this game where we are attempting to play nice with grpc-labview enums when we really don't even need them.

[pratheekshasn]

We have a test suite that covers this use case, where there are no enums in the proto file, and the tests run fine.

Register Enum Metadata.vi, as shown below doesn't run the loop at all when an empty array is passed to it.

We haven't seen any error thrown from Create And Register Server Event.vim either in all of our testing so far.

Could you attach an example of where you're seeing the failure?