Deserializing a map gives an empty map

[ovatsus]

I have a Map<string, Record>, and serialize it using:

let fsp = FsPickler()
fsp.Serialize(stream, map)

I checked the file and it looks fine, but when I deserialize it again with fsp.Deserialize<_>(stream) I get an empty map

[ovatsus]

Repro here: https://github.com/ovatsus/HouseHunter2/tree/775f6ca23627c66f05b72b23f03fc5120e965c6b

[eiriktsarpalis]

Strange, I have unit tests set up for maps. Can you verify that the bug persists if you use the Pickle/UnPickle methods instead of Serialize/Deserialize?

[ovatsus]

Adding a CLIMutable attribute to the record solves the problem, but I though that was not required. Json.NET gives a cast error between FSharpList to ICollection without the attribute, but FsPickler jsut fails silently, I would prefer it to also crash

[eiriktsarpalis]

I am unable to reproduce this problem. I used your type definitions and serialized/deserialized a singleton map using the Mock entry. Could you possibly write a self-contained, bare-minimum script that reproduces the problem?

[ovatsus]

• build and run from that commit
• click the start button
• wait for a couple of items to show up
• stop
• exit
• start and put a breakpoint in the deserialize call

[eiriktsarpalis]

I'm still pretty convinced that the issue lies with your implementation. For example, I was able to verify that FsPickler works correctly in the following snippet:

https://gist.github.com/eiriktsarpalis/e477b8c9602769c34d0f

As you can see, I create a map using your crawler implementation, then successfully serialize and deserialize using the same workflow. A race condition, maybe?

[ovatsus]

Humm, It's possible, I'll close the issue then

[ovatsus]

Thanks

[eiriktsarpalis]

Let me know how it works out, a curious issue nonetheless.

[ovatsus]

Tried again, and it's working both with and without the CLIMutable, so I was doing something wrong before. In any case I'm keeping Json.Net, performance is not a problem, and json is easier to debug than a binary file

[eiriktsarpalis]

I agree, binary serialisers is probably not the best choice when persisting data.