Why was PartialEq derive removed from DecodeError?

[reinhardbluelab]

I had a unit test that compared the returned value of bincode::decode_from_slice (using assert_eq!), but since derive PartialEq was removed from DecodeError in 2.0.0-rc2 this causes an error: Binary operation == cannot be applied to type.

Shouldn't DecodeError derive the PartialEq or Eq trait so that DecodeError instances can be compared?

[VictorKoenders]

rc-1 was incorrectly dropping underlying std::io::Errors, so those had to be added to the DecodeError as variants (#574). Because std::io::Error does not implement PartialEq or Eq we cannot auto-derive it ourselves.

I personally think that std::io::Error should implement more traits (Eq, PartialEq, Clone, etc) but this should be taken up with the rust-lang devs

[reinhardbluelab]

Thanks for the explanation. Interestingly, I see that that std::io::ErrorKind derives some of those traits.